Testing a MAF sensor??

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Apr 13, 2004 | 09:11 PM

dzierke

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From: Modesto CA

Testing a MAF sensor??

Been trying to fix a problem that started yesterday. Rough idle, wants to stall and smells like it's running rich. Also had a code 36 regarding 2 MAF relays. Changed the relays, installed new plugs, cap and rotor. Started it up and no change. Still runs like crap! I also had the ignition module tested and it checked out fine. How do I test my MAF other then a burn off check to see if it's working properly? BTW, fuel pressure holds at 50 psi when running. Any other ideas on what else to look at? :beatdeadhorse:

Apr 13, 2004 | 09:15 PM

bogus

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From: San Pedro CA

Re: Testing a MAF sensor?? (dzierke)

I just replaced one on bastet44's 87...

According to Gordon Killebrew, the earlier vintage MAFs are problematic.

Sadly, I don't have a book here to help you diagnose the unit...

Apr 13, 2004 | 09:34 PM

dtorc4

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From: Atlanta GA

Re: Testing a MAF sensor?? (dzierke)

With the car running, take a screwdriver and tap the housing. If the car seems to miss more while you're tapping it, then your MAF is toast.

Apr 13, 2004 | 09:39 PM

VettBrat

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From: Coweta OK

Re: Testing a MAF sensor?? (dzierke)

My mechanic told me to unplug the MAF. If it ran better the MAF was bad.

Apr 13, 2004 | 09:41 PM

dzierke

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From: Modesto CA

Re: Testing a MAF sensor?? (dtorc4)

Quote:

With the car running, take a screwdriver and tap the housing. If the car seems to miss more while you're tapping it, then your MAF is toast.

:beatdeadhorse: :beatdeadhorse: :beatdeadhorse:

I did understand how tapping my MAF will make my car run worse then it already does.

Anyone have a better idea?

Apr 13, 2004 | 09:44 PM

dzierke

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From: Modesto CA

Re: Testing a MAF sensor?? (VettBrat)

Quote:

My mechanic told me to unplug the MAF. If it ran better the MAF was bad.

Will try that and let you know what happens...

Apr 13, 2004 | 11:28 PM

JCAIRE2

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From: High Plains Drifter Fayetteville, AR

Re: Testing a MAF sensor?? (dzierke)

Quote:

fuel pressure holds at 50 psi when running.

50lbs. is a little high, might explain the rich condition. Only other way I can think of to test the MAF is to hook up a scanner and look at the gm/sec the MAF is telling the computer.

Apr 15, 2004 | 08:08 PM

dzierke

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From: Modesto CA

Re: Testing a MAF sensor?? (dzierke)

Quote:

My mechanic told me to unplug the MAF. If it ran better the MAF was bad.

Will try that and let you know what happens...

Unplugged the MAF as suggested and my idle cleared up. Went down to a local parts place and picked up a rebuilt MAF for $150 w/ a 1year warranty.

My car is back to it's normal self again.

Thanks guys!

BTW: The parts guy did mention the sometimes you can get it to act up by tapping :smash: on it if it's an intermittent problem...

:thumbs: :thumbs: :thumbs: :thumbs: