False EGR code ???

[jcc3inc]

Good afternoon,

My 97 with 90000 miles on it has had some EGR problems lately. After the first incident, I removed the EGR and checked and cleaned it, replacing it after clearing the code. Maybe 1500 miles later the same code reappeared.
This time I bought a new EGR and cleared the code. After maybe another 1000 miles the light came on again. This time I ignored it and in due course the light went off. A couple of weeks ago the same code, P 0401 (insufficient
EGR flow) came back.

This aft I reset again. Friend John says he read somewhere that this code can be set by other than EGR problems - something about throttle position sensor and ???

Has anyone had this EGR code reappear several times as I have had? And did you determine the real cause?

Thanks in advance.

Regards,
Jack C.

[Blue Bowtie]

Exactly what code number (DTC) was generated? There are several relating to the EGR.

[BNaylor]

The PCM module uses MAP (manifold absolute pressure) to test EGR flow. A common overlooked problem for DTC P0401 on a Series II 3800 engine is related to the PCV valve. So check to make sure you have the o-ring seal on the PCV valve. The PCV is located under the MAP sensor located on the right hand (passenger) side of the UIM plenum.