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amr530711

EGR/P0405/limp mode

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Just a note to thank the forum and share my experienceI got a check engine light, code P0405, and limp mode shortly after an oil change (the second time this has happened right after an oil change, might put some weight behind the "only fill to 3/4 mark comment)I pulled the EGR (thanks for the pictures and instructions) and it was very dirty with the piston clogged. Not a difficult job, especially after getting the Torx combination wrenches from Princess Auto, (now discontinued but they will check other stores and have them shipped to you)Cleaned it out with Gunk and Disc Brake cleaner and put everything back together. Started the engine and got check engine light, code P0405 AND P0403, but didn't get limp mode. Reset the codes but they came back instantly. Gave up and spent the rest of the afternoon visiting. (and fuming)Tried it again that evening, NO check engine light, no limp mode, but still had P0405 and P0403. Shifting seemed off with higher than usual revs (4,500) required for 3rd and 4th.Now I have no codes, and shifting seems normal. Is there a learning mode in the engine's computer when components are modified or replaced?Anyway, that part of the car is working fine, now I need to work on the parking brake! (can't you tell that the warranty has expired?)

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Now I have no codes, and shifting seems normal. Is there a learning mode in the engine's computer when components are modified or replaced?

Yes, there is some crazy shanagans that happens with these codes. While testing circuits I have had the computer lock the codes in, and the light on for three to four days, even with a perfectly working EGR connected.

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I am experiencing the same issue, I flushed the oil over a week ago, filled it to the MAX level (wont do that again) and got the code P0405 and automatic shifting doesn't always work.What can be done to correct this issue ? is the EGR valve cleaning the answer ? did i damage anythings permanently ? help !! :(

Edited by kilimats

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Yeah, you will need to clean the EGR.. Then you will need to wait a few days of driving and the light/code will reset itself.

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Also -- though not directly related to the code -- don't fill the oil to the "max" line. About 2/3 to the line when the engine is at operating temperature is the maximum.

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thx guys for the feedback, I decided to order an EGR emulator thus avoiding the need to clean up the EGR, I test drove it today and the car handles like new :D :D

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It would still be wise to clean out the EGR, as the guck may be restricting air flow. The emu will then prevent it from buggering up again later.

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I was in the impression that using an emu would make the egr valve useless, ive see some people taking the egr valve off actually and using covers to blocks the holesIf it is still used, will running biodiesel b100 for a year + with the emu clean out the gunk itself?

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The EGR valve opens and closes to allow exhaust gases to enter the intake at the pipe that connects it with the intercooler. When it opens, it introduces soot and other contaminants to this pipe, which is already carrying oil-laden air. This causes the accumulation of crud in the valve as well as inthat intake pipe. When people remove the EGR, the only hole that gets blocked is the one from the exhaust system; the EGR is replaced with a smooth pipe from the intercooler direct to the intake. If you leave the EGR in place using an emulator to prevent it from opening and allowing exhaust gases into the intake, the EGR still acts as a conduit from the intercooler to the intake. Leaving the crud in it may be restricting air flow.

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The EGR valve opens and closes to allow exhaust gases to enter the intake at the pipe that connects it with the intercooler. When it opens, it introduces soot and other contaminants to this pipe, which is already carrying oil-laden air. This causes the accumulation of crud in the valve as well as inthat intake pipe. When people remove the EGR, the only hole that gets blocked is the one from the exhaust system; the EGR is replaced with a smooth pipe from the intercooler direct to the intake. If you leave the EGR in place using an emulator to prevent it from opening and allowing exhaust gases into the intake, the EGR still acts as a conduit from the intercooler to the intake. Leaving the crud in it may be restricting air flow.

Thats great, thx for explaining how it work, do you think biodiesel will decrease the gunk in the egr valve over time ?

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Not really, no. Biodiesel produces about the same amount of soot overall as regular diesel, but because of its higher cetane number it does tend to burn more completely. However, this will have no effect on cleaning out the crud that's already in the EGR valve.

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I have had an EGR emulator in function for nearly one year (still do), and this week I started getting a PO405 code.Comments anyone?!?!ThksUGo!st

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PO405 is a problem with the valve electrical feedback about it's position, to the best of my knowledge nothing else can set it off. The emulator itself may have a problem, the wiring could be chafing. A good first step would be to clean the connector plug and inspect for obvious wire problems. Use electrical contact cleaner or any light solvent like rubbing alcohol you have around, wet the plug, insert and remove a few times to wipe any oxidation from the pins and sockets. A smear of dielectric grease helps to prevent these problems from returning.

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I got this with a wiring problem on my emulator, check the wires, make sure none are broken or shorted. If all is well with the wires I would expect a problem with one of the components on the board. Good luck.

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Got a CEL with P0405 today. It was a wiggly connector on the emulator. Pushed in and zip-tied in place. Fixed for now. Might have to pull the emulator board and do a more permanent repair later...B :drive:

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It might be time to reprogram to a different firmware in your car.... Maybe it is too early to suggest right now, but someone has to be the first.

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It might be time to reprogram to a different firmware in your car....

Could be right. My emulator was a very early version. I might even swap it out and buy your latest kit - someday.B :sun:

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I wouldn't bother. It is the same as your version, just smaller.I think it is the code 0184 from chiptuners that doesn't even look for an EGR.

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I have had an EGR emulator in function for nearly one year (still do), and this week I started getting a PO405 code.Comments anyone?!?!ThksUGo!st

The original circuit used an electrolytic 10uFd capacitor which may not behave well under low temperature conditions.If possible I would suggest replacing it with a Tantalum or a newer Ceramic capacitor which will perform better under a wider environmental range.

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You would be referring to a circuit that was not bought from me...And I could see that being a problem, the goo goes bad after a few years.

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