The P0401 diagnostic trouble code is a diagnostic error that indicates an issue with the Exhaust Gas Recirculation (EGR) system, which is crucial for reducing emissions and improving engine efficiency. It means that there is something that restricts the flow of recirculated exhaust gas. In most cases, the ECM/PCM recognizes the failure from two consecutive failures. If your car computer logs error code P0401, it means the computer has detected insufficient flow in the exhaust gas recirculation valve.
The P0401 code is a generic OBD-II error code that indicates an issue with the EGR system. When this code appears, it means that the EGR system is not functioning properly, leading to increased emissions. The P0401 error code usually means that the EGR valve is not opening and closing properly. The most common cause of this DTC is a clogged EGR filter. Driving the car too easy too often makes it more of an issue.
In summary, the P0401 diagnostic trouble code is a common OBD-II error code that indicates an issue with the EGR system, which is crucial for reducing emissions and improving engine efficiency. The most common cause of this DTC is a clogged EGR filter, which can be resolved by replacing the valve or adjusting the EGR filter. Regular maintenance and checking the engine’s oil levels can help prevent further issues and ensure optimal performance.
📹 How to Clean EGR System in Your Car (Low Flow Code P0401)
EGR system. How to clean the egr system. EGR system cleaning and carbon removal in your car DIY with Scotty Kilmer. Low flow …
Will a P0401 code clear itself?
It is possible that a P0401 code may temporarily clear itself; however, it is probable that it will recur if the underlying issue is not addressed. The EGR system recirculates exhaust gases back into the engine with the objective of reducing combustion temperatures and NOx emissions. The presence of a contaminated air filter can contribute to the development of EGR system complications over time, although it is not a direct causal factor.
How to fix EGR a flow insufficient detected?
To address an EGR issue, it is essential to undertake a comprehensive inspection of the valve and tubing. This entails a thorough cleaning of the components, a meticulous examination of the voltage at the DPFE, a comparison with established standard values, and a replacement of the DPFE sensor with a high-quality or OEM model. In cases where the EGR valve requires replacement, this should be undertaken.
How much does it cost to fix EGR flow?
The average cost for an EGR valve replacement is between $385 and $469, with labor costs between $95 and $120, and parts priced between $290 and $350. If an illuminated check engine light indicates a problem with the EGR valve, the manufacturer recommends diagnostic procedures to isolate the cause. Relacement typically involves unbolting the old valve and installing the new one. Rust can develop on the mounting nuts/bolts, so penetrating oil should be used before attempting removal.
Care should be taken around hot exhaust components and checking the EGR passages are clear. RepairPal recommends using penetrating oil when working around hot exhaust system components and inspecting EGR passages to ensure they are free of carbon buildup. Vacuum hoses and electrical connectors attached to the EGR valve should also be inspected and repaired or replaced as necessary.
What is the code for insufficient air flow?
The diagnostic trouble code (DTC) P0491 indicates a deficiency in the secondary air injection in bank 1, as determined by the PCM.
Can I drive with insufficient EGR flow?
The probability of operating a motor vehicle with a malfunctioning exhaust gas recirculation (EGR) valve is exceedingly low.
Can I clean my EGR valve?
To clean an EGR valve, spray the cleaner onto the valve, evenly covering all inlet and exhaust valves. Wipe off the spray from sensitive plastic and electrical components to prevent damage. Use a pipe cleaning wire brush and scraper to remove carbon buildups from the valve. Use a soft-bristled brush to remove waste materials and wipe them off with a clean rag. Avoid applying too much pressure on sealing surfaces to prevent leakage of trapped gases.
What is the code for EGR fault?
The exhaust gas recirculation valve (EGR) is an integral part of a vehicle’s engine management system, recirculating finely metered quantities of exhaust gas to the engine intake system for increased engine efficiency, reduced fuel consumption, and lower NOx emissions. Common fault codes on late model EGR valves include P0400, P0401, and P0402. The EGR valve works by converting nitrogen, the majority of the air we breathe, into harmful oxides of nitrogen (NOx) when exposed to high temperatures in the combustion chamber, causing it to be passed through the exhaust system into the atmosphere.
Can I drive with a P0401 code?
It is possible to operate a vehicle with the P0401 code active, but it is imperative to seek immediate assistance from a qualified service center. The underlying issue must be addressed without delay.
Can I still drive with a P0101 code?
The P0101 code is likely to affect your car’s power and performance, but it won’t stop it from running. To fix the code, check the wiring and connections between the MAF sensor and the ECU, replace any faulty parts, and replace the air filter if all checks out. Regular maintenance is crucial to prevent serious issues down the line, so follow your car’s maintenance schedule as listed in the Haynes manual or online Haynes Autofix product.
What can trigger a MAF code?
Mass Airflow (MAF) issues can be caused by various factors, including contamination on the MAF sensor, faulty or worn-out MAF sensor, vacuum leaks, or a problem with the intake manifold. Contamination can cause inaccurate readings, while a faulty or worn-out sensor can result in incorrect data being sent to the ECM. Vacuum leaks can affect the pressure within the intake manifold, affecting the MAF sensor. A problem with the intake manifold can also affect how air enters the engine, causing inaccurate readings.
It is crucial to diagnose and repair MAF issues as they can cause various engine problems, such as poor fuel economy, misfires, and stalling. A faulty MAF sensor can also cause the engine to run too rich or too lean, damaging the catalytic converter and other components.
To resolve a P0101 OBD-II trouble code, inspect for visible damage or contamination on the MAF sensor, clean it thoroughly, replace the faulty or worn-out sensor, identify and repair vacuum leaks, and address any problems with the intake manifold.
Can I drive with EGR fault?
A faulty EGR valve may not be safe to drive for a short period, but it can significantly impact the vehicle’s emissions, performance, and fuel efficiency over time. Addressing EGR valve issues promptly is crucial to prevent further damage and ensure optimal performance and emissions compliance. To schedule an appointment at a Blandford car garage, contact us to assess your EGR system and replace the valve.
📹 Code P0401 Egr Flowinsufficient Fixed !
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This article saved us $1495.00. That is what the mechanic wanted to get our 2000 Odyssey to pass the smog test. Our check engine light was on and we were told we needed a new catalytic converter, new oxygen sensors, etc. After perusal your article, we decided to try cleaning out the EGR valve port. Your article moved a little fast, but we managed to follow your steps and it worked! Our van was able to pass smog and the only thing it cost was a can of carburetor and intake valve cleaner and about an hour or so of our time. Thank you!
I cleared that dreaded code on my 99 Accord after doing this procedure, I just drove through about one or 2 tanks of gas and the check engine light went off. I found that a shot gun, or any big bore gun cleaning wire brush works wonders on those ports and gets every bit of that carbon out with a lot of help from break or carburetor cleaner. Also the throttle body was stuck on there after I took the nuts off, I used a flat head screw driver buy placing it in the notch on the front of the TB and gently pried it off with a some help from a plastic or wooden hammer. Make sure to clean the throttle body and intake manifold as well. My milage and throttle response noticeably improved.
I appreciate your website and I’m sure you’ve saved lots of people cash. I have a Prius, lost a bet, and fixed mine in the following manner. I had cleaned everything, but the code was still there. If you pull the plastic cover off of the engine, on the right side, you’ll see the black cover to the egr valve. Wiring harness, and two Phillips screws, in plain sight. I removed the two screws, and unscrewed the cylindrical magnet with the bearing. If you clean out the grease from inside the magnet, you’ll see a little nub that wears down. I simply put a washer over the threaded rod, thus extending the throw of the valve to a pre-worn state. It WORKED ! Seems the travel of the plunger gets shorter and sets the code. Hopefully this will help some viewers. All I ask in return, is for smokers to use ashtrays, and not the highways or parking lots. C’mon America, take pride…
Scotty most of these Honda V6 engines have a TSB and some a recall on this. This cleaning of the EGR ports maybe just a temporary fix until it plugs up again. I purchased the Honda 2 step drill to reshape the inside holes and there is a special tube that also is installed inside the intake manifold. Keep up the great articles…
Mr Kilmer, thank you for your articles. My 97 Malibu was not passing emissions, with 2 codes one was this code (P0401) the other was a cylinder 1 misfire well needless to say that I put over 200 dollars into the car to get it to pass. New egr valve, plugs and wires, coils, ignition control module. Which the last of the list from plugs and on i needed to do anyways, Im upset that I got the new EGR valve when not needed. Yes the car passed today. you sir have a new subscriber
Hey Scotty, great article. Im doing this fix to my aunts 99 odyssey. I cleared the code and ran it for a couple of days. Now the same code is back, so I’m guessing its the EGR valve itself. But I was wondering if you would recommend cleaning the actual EGR valve before replacing it with a new one. I’m doing this in effort to save her some cash. Thanks.
Thank you SO! much for posting this! I was worried that dissolving all that carbon build up into my engine would bad. You showed how it all just goes out the exhaust. I spent 5 bucks on some hose and carburetor cleaner and my car runs better than when I bought it 9 months ago (guess their service center didn’t bother to check the EGR). They wanted over 250 in parts before labor to replace it … I MUCH prefer your D-I-Y method rather than throwing half a months rent at the problem!
Good article. I had a P0400 on a 96 geo metro and it turned out that the EGR valve vacuum solinoid was not working rite, I just replaced that today and now i got to go through the drive cycle cause i reset the MIL. The dealer wanted $225 bucks just for the part, I got a very good used one at a junk yard for $5. 🙂 Wish me luck i hope it’s fixed. Thanks for the awesome articles scotty!
I found the main air intake was loose at the throttle body..one of the codes warned of intake pressure…also a large harness/ connector that clips into the bottom of the cam chamber wasnt clicked fully in… Ive pulled the battery off to reset the ECU….lets see?…either way a lesson in making sure its all tight back down! Your the man!
I have a Toyota 3rd gen Prius. I used an extra reach 12 mm racheting wrench for the three Nuts in the back and had a hard time reaching the 4th HIDDEN 12 mm nut underneath the EGR cooler. Used a Torx E8 socket for the two Bolts ( in the back of EGR cooler) and we finally freed the EGR assembly. Good article 1
The mid 90’s Ford 4.6L’s are notorious for this problem. It gives a false code of a bad EGR valve when in reality it’s a clogged/dirty intake. I fixed it once yet happens again several years later despite proper tune-ups and running top tier gas. It runs fine no matter what, I just have an annoying check-engine light again. Of course Ford fixed the problem the model year AFTER my car. One mechanic told me to leave it alone, he said I am actually getting somewhat better mileage yet it won’t pass inspection if I move to Cali or Texas. Luckily I live in Iowa and am staying put. On an unrelated note, like you Scotty I keep my cars a long long time. The places I have lifetime warranties at hate me. Lol.
Dig the enthusiasm. I did a lower intake manifold gasket on a GM 3400. Now I have a burnt oil smell coming out of the EGR after running at highway speeds. I’m not burning any oil (checking dipstick). No rough running and no codes. Put on 500 miles since the work and is still happening. PVC is good(rattles).
Thank you Scotty! I just wanted to say I tried all these tips, even had Ford take a look at it (and I STILL HAD THE PROBLEM!!!) Then I took a look at it again and it turns out the gasket after the throttle body was cracked and letting air through. I don’t know how I didn’t see that earlier (I had removed the throttle body a good 3-5 times) Long story short, I went to my local auto zone, bought the gasket (<$2), put it on, started driving around and my 96 F150 gained a good 1-2 mpg (I'm at around 12 on a good day without road rage, haha) and stopped idling roughly, not to mention the code was no longer there! Hopefully this can help someone else if they have a similar issue. I love your articles, Scotty, and you gave me the confidence to start messing around under the hood and luckily my final fix cost me about $2 and had someone else done that for me I know that would've been well over $100!
Honda has a special drill (one that wont let you drill all the way through the manifold) to open up that passage, and increase the diameter of the hole. There’s also a smooth looking sleeve you press into the hole, and that’s supposed to prevent carbon from sticking to it. I must have done a hundred of these as a Honda Tech. Cheers!
Oh and one last thing Scott’y.I did take off the egr valve and it was really dirty so I cleaned it out with carburetor cleaner and a baby bottle brush.Because you can get into all of the nooks and cranny’s with one.When I got done it worked just like a new one.The reason I know, is I went to the parts store and checked out the suction on the new one and after I cleaned out mine they were exactly the same suction pressure.
I finally put my big boy pants on and searched for the vacuum leak again. It was the tiny hose where the pcv valve meets the vacuum line.I just squeezed the foam cover and the hissing stopped, eureka! Replacing that 3 inch hose got rid of the leak, got rid of the check engine light, and the engine doesn’t misfire anymore, runs really smooth.
Took a second look and the coolant is normal..duh. Removed the intake a second time to double check and everything is clean but still getting the p0401 on my 02 Accord 3.0 with a new EGR valve. What am I missing? I really can’t afford to put it in a shop so I’m hoping to hear something. Subscribed to your website today because your vids are always helpful and btw yours is the only website I’ve ever subscribed to. I’m from Houston and used to see you on website 11 I think it was so I was glad to see you started making these articles.
I removed the egr valve on my Honda accord 2000 v6 and cleaned it but it seems the intake itself is still clogged. I haven’t done the full clean yet because im afraid the gasket for the throttle body will break. I saw it doesn’t cost much so I’m going to buy it soon. Are there any other gaskets I should be worried about in this fix? Thanks Scotty!
I have a P401 code on a 2002 Mitsubishi Montero Sport 3.5L 1. I replaced the EGR valve and it didn’t fix the problem. 2. I took off the cover and cleaned the inside of the plenum. Didn’t fix the problem. 3. Bought a new MAP sensor and didn’t fix the problem. 4. I took off the hose to the Vacuum Control Valve and plugged the hose and hooked up my hand pump to the VCV port and it read 6.5 5. I hooked the hand pump to the EGR and pumped to 8.7 and the car ran rough.
Hey Scotty, I have a kia Sorento 2.2 credit 43k on the clock, developed a p0404 code. can a EGR clean fix the loss of power. Kia motors wanted to replace the egr valve, saying it was seized up, then a quick code delete after to finish off. Any advice is appreciated. I’ve learnt a lot off of you, keep up the good work. Not all heroes wear capes!
Just cleaned it in a 94 TownCar and it cleared the code on the EEC-IV computer (paper clip method). Then I discovered the aluminum hose connector coming out of the EGR valve was broken (Hint: way too hard for me to reach, especially for someone who did a DIY solo first time). It had some marks indicating it had been broken for quite a long time, so I assume now that I may have to stop doing business at the mechanic my dad’s been doing business with (this and several other repair goofs overtime).
Great article, I had to change one in a ’94 Ford Ranger pick up with a 6 cyl manual and it was a piece of cake, I now have a 2008 Ford Ranger with a 4 cyl automatic with a P0401 code check engine light, it went off for a couple months and tuned back on a few weeks ago so I bought a new EGR valve and thought it was going to be a piece of cake, until I found out the EGR valve is located on the back of the engine against the fire wall and the transmission cross member has to be unbolted and lowered along with the exhaust pipe and drive shaft, I was wondering if I should apply some Permatex copper coat on the new gasket since there is a water passage through the EGR Valve or just install the gasket without gasket sealer.
Scotty,,,, I got a V6 Ford Tempo. It runs like dream but last year I blocked the EGR valve just to see if I get more power and I put in a piece of wood in the EGR valve’s outlet to make sure dirt will not go into it. But this year I decided to put the EGR valve abck the way it was and the top of the wood broke and the piece of wood fell into the EGR valve.CAN IT MAKE ANY DAMAGE TO EGR VALVE?
I appreciate the response. I’ve been through one EGR already, the new one didn’t fix the issue. (approximately 2 years ago) Civic LX Sedan 1.7 liter 4 banger. I recently cleaned the hell out of the EGR, and EGR passages as well as the manifold – it’s no doubt clean. I’m hoping it’s not the EGR again – but if it is, then it is. I was wondering if there was a way to check the EGR valve itself? Also the Solenoid of which you speak, how easily do they go bad? Thanks for your time.
Good fix.The egr valve signals 0.5 v to Ecuador when closed and 5 volts when open and flowing normally.A 2 dollar circuit can be built to foll the Ecu but there is also a cheaper eat for Honda with egr 1433 valve 2001 accordThe gasket for the egr has a round hole for plunger and square for egr glow output.Take 4 gaskets possible 3 and silicone into one thick gasket and cut the outer edge to square/rectangular holeNow get a washer of suitable thickness and cut it half and place ar corners of court out with gasket and egr installed and tighten. Cut washers should just fit and be tightThe exhaust will now flow giving 5 volts to ecu
Thanks for the information and pictures ! …I guess all I noticed is that I thought there was a sequence and a torqe spec for the bolts that you needed to follow when you bolt the intake back on.. starting to tighten from the middle and work out,so as not to warp the intake.. but.again, thanks for the excellent article !
I have a 1997 F150 4X4 with the P0401 code. I have some mechanical knowledge and I was able to remove the whole TB and clean out the EGR ports because they were completly clogged up with carbon. (I know these F150s are known for the P0401 code) After putting it all back together and clearing the DTCs It came back again a few miles later. Could the valve be bad or the DPFE sensor be a probable cause too?
Hey, Scotty. I have an F150 with the 4.2l engine. I took the plenum off but it looks like the ports are on the lower intake. Could I just try my best to clean them with carb cleaner and compressed air or should I remove the whole manifold to clean both sides of the ports? Looks like a whole lot of work.
Soctty. I did a method on checking the egr by pushing the plunger and placing your finger tip on the tip. If plunger moves its bad, if it stays its good. I cleaned my egr thoroughly and light came back on. Car idles rough at stop but drives fine. but get this…. When i unplugged the little hose connected on the nipple of the egr valve the car idles smoothly. Why is that?
Hi, will this work for my 2001 dodge stratus, it has a v6? Also after you reset the computer exactly how long and at what speed do you have to finish the reset process? Please give me as much details as possible because people are telling me you have to drive it for 50 miles at exactly 50 mph. Thanks
I had the P0401 code and like i should do, i cleaned my EGR chamber, ports AND egr Valve and gasket. pretty much all I should do. However I did not use a shop vac of any sort i jus sprayed carb cleaner through the ports to loosen up the carbon buildup. The amount of carbon buildup was RIDICULOUS almost full to the top in the chamber. Anyway I made sure the ports and everyhting were clear and clean(with a allen key and carb cleaner), however IM SURE some/most of the carbon has fallen into the intake manifold. So i take it for a little spin – 1st gear is as powerful as it can be plus im getting ALOT of torque steer and power when i hit vtec. i noticed it hits in earlier which is perfect BUT – 2nd gear rolling to full throttle i notice that the rev bar kinda SLOWS down significantly and hesitates at around 4000rpm to 5500rpm. When it hits vtec however everything is normal and all power. I am thinking is this a result of carbon buildup falling into the intake? NOTE: I DID NOT take it for a spin on the motorway like you said. Would that help? Thanks Scotty
This would definitely work for a GMC vehicle with the 4.3L “W” CPI engine found on approximately 1/2 of all six cylinder 1994-2003, S-10’s, Sonoma’s and 1995 through 2005 Blazer’s, Jimmy’s and Bravada’s along with Astro vans and Chevy 1500’s too. In fact, Napa and Autozone sell a screened gasket between the EGR valve and the intake to reduce the passage of carbon and inevitable clogging as noted in the article.
I have a 96 Ford Ranger and I got the p0401 code I replaced the Egr valve and took the truck for a drive probably around a hours worth and the light came back on should I do the same thing you did in the article and try clean the intake manifold and maybe even the throttle body aswell as I researched and was shown the pdfe can go bad is it worth replacing and should I aswell clean the intake etc?
Scotty, My 2000 Honda Odyssey starts to accelerate back and forth when idling in park. I’ve just cleaned the carbon and replaced the egr valve as I have gotten tired of always cleaning it out and hoping that it has fixed it now after I’ve done that it manages to runs worse than before. Any Ideas on why it always starts to alternate throttle I have done this before and fixed the surging but forgotten what I’ve done to fix it before.
I watched some program on TV that said any car can run on alcohol and that there are conversion kits to run on alcohol and gasoline, just like flex fuel cars. My question to you is: Are these kits worth it? Would you recommend installing them on cars? I saw some articles on Youtube of installations of these kits being installed on different cars. What is your take on this since gas is almost at $5 a gallon???
I’ve got a 2005 Honda Civic. Originally when I pulled the code it was P0401. I pulled everything apart, cleaned it, and put it back together. Cleared the code, drove around for a bit – now I have the code P0404. I’m wondering what I should do now, since I’ve cleaned everything that I can think of. Sure hope you can help.
Hi Scotty, got a 2006 Ford Taurus with CEL for EGR (according to Advance Auto). No other problems and just turned over 100k last week. Was thinking of Seafoam in gas and intake line – afraid to put it oil. Would using the seafoam do the trick on the EGR or should I pull it off? Thanks and I’ll try to remember to “tune in” Saturday.
Hi Scottykilmer, Your article is very helpful for newbies like me. I’m also having the same error code on my Honda Odyssey 2000. I have already tried cleaning up the ports in the manifold and the erg valve and port itself but the light always come’s back on. Any ideas on what should I check next? Also after cleaning the EGR valve i noticed my car is now vibrating when running at low speeds. Any ideas on what caused this? Do I need to replace the EGR valve or is it something else. Thanks.
From what I have read, it is extremely rare for it to be a computer software problem on this particular vehicle. I think there is an actual problem somewhere because her mileage has tanked and it runs rough in idle. If you combine that with the p0401 code, does that indicate anything to you? Catalytic converter or O2 sensor? Or would those not pull that p0401 code?
Scotty, thank you for the awesome articles. I have definitely learned a lot from you. I have a 1999 Accord V6 and I took off the intake plate and cleaned the EGR port thoroughly, I took the EGR valve off and cleaned out the bottom of it where the passage is – careful not to get throttle body cleaner on the top part (electrical portion). Put it back together, took the car for a long drive and the light came back on. How can I check if the EGR valve itself is good? Could it also be an electronic thing like the computer throwing codes? The EGR passage is very clean…. Thanks Scotty
Getting the same error on my Expedition 98. I get the gist of it but would you recommend me to clean the whole throttle body? In the Expedition is a bit different the assembly so any help would be much appreciated it!!! Thanks! PS: The fix for the turning light switch worked! It was just the relay, got a new one and is working wonderfully. You’re the best thanks bro!!!
I just bought a 99 Eclipse, the previous owner took the car to the shop and I believe they cleaned out the EGR valve, cycled the engine, and passed inspections. 100 miles later, the check engine light is back on, too to O’Reilly’s for a scan and pulled the P0401 code again. The man working said it could even be the fact that it’s less than 10 degrees outside here now can cause it to come on and to see if it goes away when it warms up. Any help?
I have a 1996 Honda Accord V6 2.7L and have the same code. Is the intake manifold in a different location, because the cover is not plastic as you show and it looks like there is lot more stuff to remove to get the manifold out. Can you please let me know if the 1996 Accord V6 engine is similar to your article, so I can go ahead and follow your instructions.
Scotty when that pray liquid falls into the engine and mixes with the oil will it mess up the oil? I was wondering if maybe you could make a article of the most common things why most cars wouldn’t pass an emissions test. I remember once failing an emissions test and the car had no check engine light and I kept it in good working order. It was frustrating.
Hey scotty, I have a 2000 Honda accord v6 with a very intermittent issue. My car starts up beautifully when cold, idle at red lights, stop signs etc.. beautifully also. Runs great! But when it is started multiple times after going around town, the car starts but immediately the rpms drop so low that it starts shaking then stalls. Try and turn it on again same results happen… eventually the car will stay on, but its real annoying. Check engine light is not on. Dealership cant find out whats wrong, they cleaned the fuel injectors, I put seafoam in the pcv, fuel tank. Used a tank of premium gas. Fuel injector cleaner. But the problem continues. Now keep in mind its very intermittent… doesn’t ALWAYS happen. Have any advice? Thank you
Hey scotty, My 98 Honda Accord 5 SPeed 4 cyl. Has been bogging lately. Mostly in low rpm’s. I juust replaced the fuel pump today since it was under warranty, put new spark plugs, and had even bought a new map sensor but that didnt solve it so i returned the map sensor. The map sensor improved the issue but didnt solve it. My intake manifold is squeaky clean also. When I drive, at time it feels like im hauling a boat . My timing isnt done on the car but this problem didnt happen before.
Hi Scotty. The article was a great help !.I pulled off the intake and cleaned out the egr ports on my 98accord EX vtec v6, pulled off the egr valve and made sure it was clear back to the intake port.then I erased the code and drove it for several miles. unfortunatly after about 50 miles,the check engine light came on and the code popped up again..P0401 insuf egr air flow..also got a P0420, ineff catalyst …any suggestions beyond pulling it off again and rechecking for a clog somewhere.?
I have Honda van with P0401 code, Have cleaned plenum and intake and removed egr and blew air thru all ports after I had cleaned them thoroughly and still have dreaded code. So I ordered a new EGR still coded, so I took plenum off again and sprayed cleaner and compressed air and still have dreaded code. Any other ideas would be greatly appreciated. I run a small shop as my second job so I would like to think I followed your info correctly. Thanks mike
Hi Scotty, I own a 97 Honda Passport and i recently purchased the repair manual. It says the EGR valve on the car is different from the usual EGR valve. They are calling it a LINEAR EGR valve. It states in the manual that there is no way of checking the valve yourself and you have to take it to a dealer service. Could you elaborate on the difference between a LINEAR EGR VALVE and a normal one? Would i still be able to perform the cleaning process that you did in the article to remove the P0401?
Scotty, I have a Buick 3.8L that is giving me P0401. This is the only code coming on after I swapped out Upper intake plenum, Lower intake gaskets, tensioner’s elbow coolant pipes, Valve cover gaskets, air filter, thermostat, and both Radiator hoses. Point is I know for a fact that that lower metal intake body is thoroughly cleaned. If intake body is cleaned, what else can I look for in GM’s 3.8L V6 for P0401?
hey scotty i took ur advice and went to my local shop with a good expensive scan tool annnd nothin, no codes, so at this point im baffled my only other solution may be to take the intake off and egr valve and really give em a good clean down or maybe buy a new dpfe, put it on and test the voltage and see if it actually is normal with .8 volts, ideas? suggestions? always like ur advice
Hey Scotty, I have a 97 Dodge Intrepid 3.5 and was wondering when you take the throttle body off, there’s two of them that connects to the plenum, can you spray in all the holes on the plenum? Like where the PCV valve connects into. Just trying to see if I have to be careful with throttle body cleaning fluid.
Hey Scotty! I blanked off my EGR as it was always sooting up…now im getting MAP sensor and throttle position sensor warnings..I recently cleaned my Throttle body too….breaths like a dream….would cutting off the EGR cause such errors as a result of the car getting more clean air?….i really dont want to have to buy new sensors 🙁 many thanks Marty
Easiest way to clean the passage on this style V6 Honda is to remove the EGR valve and spray cleaner into the port that leads to the plenum. Make sure the throttle body is held open and shoot compressed air into the port. Have someone put their hand over the air intake to tell you when they feel air. That let’s you know when you broke the clog and its clean.
I replaced my EGR valve on my Tacoma 2002 4 cyl. P0401 pops up again. I checked the hoses and they are clear. I want to remove the air box and throttle body but I want to be sure before hand that its pretty much the same for the tacoma as this honda. It looks different. And its connected to a lot more than that honda is, making for a bigger project. Any advice? And thanks for the vids. Very helpful.
Hi Scotty… Say your article… Didn’t seem that difficult at all. Took the plunge and did the job on my 97 Acura 3.0L CL. I tell you, I was not very difficult at all. I did have to go out an buy additional cans of TB cleaners and gaskets….Other than that I was an easy job. Thanks Soloman36. Dallas. TX.
I am going to do just that, but the engine starts to power down at 2000rpm AFTER it is at operating temp, then surges when i step on the gas harder. I have codes P0170(fuel trim malfunction Bank 1)and P0171(system too lean Bank 1) for a 3.0 VTEC, which i am pretty sure is causing it. Will a vacuum leak cause the codes and the engine issue I described? Great vids by the way!!
Is it normal when put smoke to the egr valve hole which connects to intake (exhaust gas out hole), the smoke comes out under the diaphragm (breathing hole) ? When put smoke to the exhaust gas in hole( which connects to exhaust ), there is not smoke coming out. I’m a Newbie. Thank you Scotty and everyone.
6. When I hooked the hand pump up to the EGR it read zero with the engine reved 7. I took off the green striped hose on the other side of the 3 connection plastic piece going to the EGR solenoid and it read 5.5 with the engine reved. Tomorrow I would like to test the EGR solenoid out of circuit by connecting a 9V battery to it. Does it matter how I hook up the battery to the solenoid. Don’t think it can damage that solenoid with just 9V. *** Any ideas or instructions Scotty would be great.
scotty i really need your help here. my car has this problem and i dont have the car experience to attempt this. ive called multiple shops and they all tell me different things. -clean flow by injecting cleaning solution into the egr -opening intake manifold and doing what youre doing -replace sensor idk which one of these will do the trick and i dont want to waste money fixing non-issues. the car i drive is a 2001 lincoln ls, can a diagnoses find which one of these fixes i need to buy?
Hey Scotty, I have a 2004 Honda Accord with 223,300 miles. It has never had a valve adjustment in ALL those miles. I plan on doing it b/c I hear some valve chatter and clicking. Would it be alright to just replace the valve cover gasket and spark plug tube seals? Or do I also have to replace the Intake Manifold Gasket? What about the Intake Plenum Gasket? Throttle Body Gasket?
So, Scotty, I have a 98 Honda Accord EX 6cyl with a code for P0401. Used your vid to clean the EGR ports and replace the EGR valve. Now, getting code P0420, O2 sensor. Could bad EGR flow cause an O2 sensor to go out? What do you think? Is it coincidence, that the O2 sensor would go, during EGR repairs?
This is a 98camry4cyl.AT. While taking off throttle body accidentily put a small crack in the tube leading to the air box. Tried to fix it w/ permatex. (part VERY expensive). Shortly after, got a egr code and replaced the vacuum modulater which was making a lot of noise and was bad,but told the egr was “good”. But, a week later the P0401 code came up. What do u think i should do next?
Hey scotty! Kool website. I have a 2000 dodge caravan 3.0 v6. When I first turn the car on in the morning I have to pump on the gas for it to fire up.its not all the time that it does this. Other times without pumping on the gas it comes on but it hesitates and shakes. My mechanic replaced the crankshaft sensor and that was not it. Ive been doing some research and iam thinking it has something to do with either the intake, throttle, exhaust valves or distributor. Help lol
Hi Scotty, How would you test a MAP sensor to see if it is functioning correctly? I have a 1990 Chevy Lumina passenger car with a 3.1 engine and it is running very rough especially in idle. Sometimes it even stops. The engine rpm’s will also fluctuate at start up. Sometimes the car will run okay for about 10 minutes and then it will start running rough. Since it has an OBD 1 the scan tool shows a number of sensors that maybe causing the problem. I have replaced the O2 sensor about a week ago because that also appeared on the scanner and unfortunately it is still showing up even though I unplugged the battery. The scanning tool also says that the MAP sensor should be checked Thank you for your suggestions.
I cleaned the throttle body to my 2000 F-150 after getting an EGR code. The ports to it were completely blocked off with rock like carbon. After putting everything back together with new gaskets, I found that the truck shakes when I put it in drive and accelerate. Im sure I put everything back correctly and can’t find any vacuum leaks. The EGR code is gone but now I have P0136 and P1131, what did I do!
Hi Scotty, i need to ask you a question on a corolla e12 2.0 110k is necessary to purge the injectores after take of the rails of the injectores ? i´m asking this becouse i´m thinking about to take off the inlet manifolg to clean all the carbon deposits .. And becouse i dont know, in common rail injection sistem works or just bleeds it self .. thank you very much ..hugs from portugal
I saw it immediately after this one 🙂 but I don’t smoke. I left it alone and was planning to take it to a mechanic today cause he has a device that’ll emit smoke where a leak is, but on the way, my truck was driving fine, so I decided to drive it on the express way and around town for a bit, it wouldn’t shake while accelerating or at the stop light anymore… strange. I unhooked the battery to reset the computer and after 40 minutes of cruising the light didn’t come back on.
i tried this in its clear i can hear the cable in manifold just slapping around wat should i try next, n also i got a 300 2.7 06 i didnt water pump but auto zone told me to set the timing on the wrong side most people telling me my valve are bent without checking it i tried to check psi and it 0 psi on all 6 cylinders i just wanted to know if my car not timed right will it show compression on a tester i need to know b4 i go buy a engine
Scotty, I followed the article exactly and cleaned it all out. it was very clogged. I put it all backntogether, unplugged my negative terminal on battery to reset engine light. I drove about 10 miles and check light came on.. still same code along with P0420. I. was also told by a guy st adv auto to drive about 200 miles and see if it goes off. is the actual egr valve bad? I drive.a 1999. honda accord v6
But what side effecte could I see after canceling EGR ? It’s ok to apply a blank plate without cancel this valve from software ? How will be the fuel consumption after this ‘tweak’ ? I just did this modification and I run for several kilometers, but still no changes 🙂 Maybe some better torque on low RPM(1.6 16v 105HP petrol engine, on VW golf 2002)
Hi Scotty, I have a 2003 Honda Civic EX. I had the head gasket replaced, and timing belt replaced, when getting it back the po401 code came on, i’ve turned the code off but it comes back in within about 10 miles of driving. My mechanic said he replaced the intake manifold gasket with a new one when getting to the head gasket, is it possible he replaced it with the wrong one? Or perhaps just left some dirt behind in the EGR passages? Good news is coolant level is now fixed, bad news is im in NJ, and have this code on before inspection next month. Thank you.
Hi Scotty I have a 1996 nissan pathfinder with the same code I used a vacuum tester and the car did not die, it just misfired like wanting to die, my question is what to do next? I am going to start removing as much stuff as i can to clean that black stuff, thank you and any suggestions would be appreciated once again thank you
Hi Scotty, My daughter has a 96 toyota camry 4 cylinder with this code.i took the egr valve off and cleaned out the 3/4 clogged port that attaches to the car.Put it back on and the code still popped up 20 miles after driving.Could the valve be sticking? Or do these valves actually go bad?Any suggestions will be appreciated. Tx Scott
You should also take off the egr valve here and make sure when you spray through the intake port you can see it coming out of the egr port or vise versa, you can also check this by blowing air through and see if you can feel it coming out both ends…I had to do this twice because I didn’t think it was even possible to be that clogged. It was a 99 odyssey and the ENTIRE intake port was completely locked with carbon. Ended up using 2 cans of carb cleaner to get it all cleared through
@founditnow54 They are technically called “beauty covers” and I agree, they are stupid,. But many people expect them to be there when they open their hood, so put them back on (except on my own cars, where I don’t have them cause my cars are all old and they never used to put the stupid things on.) scotty
Have a bit of a problem my car keeps producing a power reduce and service engine soon light. I just replaced the intake gaskets, map senaor, cleaned the mass air flow sensor and throttle body. Even checked all my wires and when complete it drove fine fpr a second then began to sputter and die as well as all those previous lights came again any idea???
Hi Scotty, I did exactly what this article shows, but the code came back on. I read the bottle and it says to repeat the process.a few times. Light still comes on when i reset it. What can i do? The egr valve held pressure when i tested it. My tags are ’12 and i need to get the ’13 before i end up with a ticket. What can you suggest I do?