P0402 code after EGR Cooler Replaced

[darrell8]

I have a 06 F-350 I had to replace the EGR Cooler. After the cooler was replaced I had a CELL come on and the code reader is getting the P0402 code. It says EGR FLow Excessive I have read on here that it could be my EGR valve I had just replaced the EGR 2 weeks before the cooler. Could the coolant flowing through killed my EGR? I ran the truck some after the I began to get the white smoke or steam from the coolant burning so I didnt know if that would have killed it or not. What else could it be? I read something about some other kind of sensor that could be bad but dont know how to check it or where it even is on the truck. I am reading any freeze codes showing the truck is running in any limp mode from the Cell. The truck is running fine just the light is annoying to have on all the time. Any help would be great. Thanks

Guess I should have said the only mods I have done is a Airaid air intake kit. Everything else is factory.

[darrell8]

No ideas at all

[darrell8]

O come on guys give me some ideas on what I should try. My EGR valve has a 12 month warr. or 12000 mile on it I can get a new one if you all think it could be the valve. Any help would be great on this I am tiried of looking at the engine light.

[Robsr]

You'll need to look at ENHANCED data. data log the egr and see if the PCM is commanding and what the position feed back is. then you'll need to look at IAT2, see if the sensor is skewed and sending a false voltage to the PCM. this is how flow is determined-uses the IAT(1) in the MAF and compares it to the IAT(2) in the intake.

If there were an issue with the EGR valve circuitry itself, it would or should show up during a KOEO test .

there might be other related codes in PCM memory that you are not able to access with a code reader. dunno, never used one.