Check Engine Light - What the #*&&!! (1 Viewer)

[madams557]

Thanks Semlin, I happened to print of the FAQ post after I submitted my response, and it didn't seem as bad once I read it.

I'm going to start working on identifing where my EGR problem lies this week. I'm wondering though if I don't find carbon in the EGR modular, then what? The FAQ covers what to do when carbon is present.

If I don't find carbon, should I start saving my Kool Aid points now so that I can afford an EGR modular in a few months??

 

[semlin]

if no carbon in the modulator filter then the problem is less likely to cause you longterm damage if you ignore it. there are several possible reasons for the code but the next place i would check would be whether there is blockage in the pipe that runs inside the intake plenum from the EGR valve to the air intake. There are photos of this. To check it you need to pull the egr valve and the throttle body. this is a 1 banana job which also gives you an excuse to clean your throttle body which at 190k is probably overdue.

 

[Rookie2]

One of the other common causes for the PO401 is the VSV for EGR. My P0401 was intermitent over about a 6 month period with the reoccurence frequency increasing over time. A new VSV for EGR seems to have fixed my problem. But I first removed and cleaned the throttle body, not because I thought that was the problem, but because A) it probably needed it anyways, B) it couldn't hurt and C) because it the easiest way to get the VSV out and test it. Although the test didn't seem to show a falty VSV, since the CEL was intermittent I went ahead a took a stab at it and replaced it... and no CEL since.


Rookie2