94-100CS-inWI

I have a 94 100CS (2.8 V-6 FWD) with only
28000 miles (mother in law's former "Sunday
church car!). When the engine is warm and
I get into city traffic the check engine light
comes on. If I am on the highway it does not
happen.
My commute takes me at highway speed most of
the way with one village in between with a
25mph limit. The light will come on there and
once I am out of town it goes out.
Any thoughts would be appreciated!<p>94-100CS-inWI

fabio

This problem occurs quite often when there is a vacuum leak. The vacuum hoses will warm up, get soft, and start to leak, usually setting off the check engine light at idle or stop and go driving. The check engine light is activated because the mixture is too far out of specs for the oxygen sensor to compensate for, and I bet that is the fault code you would find. Let the engine warm up, remove the top cover and check the vacuum lines that are located on the left hand side of the engine (right as you look at it from the front of the car) and listen for a sucking or whistling sound, or gently wiggle and squeeze the hoses to aggrivate the leak.

ARK

What is the Diagnostic Trouble Code?