Mass Air Flow Sensor Problem

WANDERER529

MEMBER
2002 CADILLAC ELDORADO
4.6L
V8
FWD
AUTOMATIC
126,000 MILES

I have been getting PO101 trouble code which illuminates the MIL. I have replaced the senor twice with no solution to the problem. Sometimes on start up, the cold engine will not race, sometimes at idle in gear the rpm's are about 200 rpm's higher than they should be. The MIL may not be on at this point but I know that sooner or later it will. The engine has been "smoked" and no vacuum leaks have been found. There are no real driveablility issues. When I clear the code, the idle in gear and in park is normal for a short time and then the code returns. I will check the intake snorkel and PVC next. The enhanced Cadillac code says voltage out of range. Do you have any other suggestions on what to check? I am totally frustrated and nobody seems to have an answer. I hope you guys do!

Thanks for your help!

1 Reply

HMAC300

MECHANIC
48,601 POSTS

Check items in picture it may be a vacuum leak by map sensor or the intake air temperature sensor or EGR possibly not working right or partially clogged. Clean throttle plate as well on both sides and IAC hole with choke cleaner. See picture.

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