Bad MAF????

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Oct 27, 2007 | 01:30 PM

gfunk

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From: fresno ca

Bad MAF????

99 coupe with 74k
its getting a lean signal so its dumping fuel, running rich. getting black soot on the back end of the car, spots on the ground etc...
took it to mechanics, hook up their machine to the on board computer and went through the system looking for clues. The only thing that stood out was the fuel , said it was toooo rich.

My question is, can the MAF and/or the Air Intake Sensor be causing this problem without making the engine light come on??
Im not sure if I should just replace the MAF or look elsewhere. Hate to spend money and replace parts that dont need replacing.

thanks

Oct 27, 2007 | 01:58 PM

87SAM

Safety Car

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From: Boise ID

Has the MAF been cleaned and inspected?

Oct 27, 2007 | 02:07 PM

gfunk

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From: fresno ca

yes, when I recently had it off, I sprayed and cleaned it with carb cleaner and cleaned in out, and gave it a light blow. the three sensors were still intact along with the honeycomb mesh stuff, I didnt see anything out of the ordinary.

Oct 27, 2007 | 02:29 PM

Y2Kvert4me

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From: Gone

CI 6-7-8-9-10 Veteran

St. Jude Donor '03

Sounsds more like an 02 sensor issue.

Oct 27, 2007 | 02:40 PM

gfunk

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From: fresno ca

we looked at the o2 sensors, and he said they were all working, and there are no trouble codes on the DIC, one was a little lighter on the voltage (or whatever) be he said they were all working.

Oct 27, 2007 | 03:44 PM

BATM4N

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From: USA

Oct 27, 2007 | 06:44 PM

JerriVette

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From: Bergen county NJ

Change out your pcv valve.. check for vacuum leaks, put on new spark plug wires..

I find I have a similiar scenerio to what your describing when one of my spark plug wires are loose..

I don't know why but if I take them off and put them back on.. the soot on the back of the tailpipe etc stops..

The tech II doesn't always help in these scenerios...

Go for the basics and you might get lucky and find the solution very inexpensively..

also having a GM decarb procedure couldn't hurt either..