is my maf sensor broken

CPTON · 01-09-2006, 12:12 PM

i tested my maf sensor as per bentley for my 95 318is.

there is a "vane" flap door that meters the air and when you probe terminals 1 and 2 your suppose to get a fluctuating resistance. well i tried this and all i got was a constant resistance, but my car runs good most of the time, the occasional stall coming to a red light and a recent problem starting.

thanks for any input

Jeron · Jeron's Garage

Sounds bad to me. Unless it is VERY expensive I would replace it.

I read the starting problem post. Have you had any luck diagnosing the starting problem.

CPTON · 01-10-2006, 08:50 AM

i started it but i didnt fix anything

CPTON · 01-12-2006, 06:38 PM

anyone?

topless318 · 01-20-2006, 04:21 PM

Mine is down too. I used my Peake code reader and the onboard light test and both pointed to my Air Flow Sensor. I just ordered a Bentley Manual so once I get it I will further test it. I would like to learn how to do the Vmeter test so a stay in the warm garage is in line.
I replaced my Air Flow Sensor back in 2000, not too long after I replaced my O2 sensor.
From what I can tell 6 years, 60,000 miles is not out of line for these parts.
Is this what others are seeing?

CPTON · 01-22-2006, 05:12 PM

does your car still run?

Dave at Pelican Parts · Dave at Pelican Parts's Garage

Quote:

Originally posted by CPTON
there is a "vane" flap door that meters the air and when you probe terminals 1 and 2 your suppose to get a fluctuating resistance.

Usually that's a fluctuating resistance as the vane inside the MAF moves. It wasn't clear if you were moving the vane or not; and if not I would expect there to be no change.

But this is from sources in "other cars", not in E36 Bimmers. I could be wrong about what they mean...

--DD

CPTON · 01-22-2006, 06:18 PM

sorry yes i was moving the vane while probing, just like how you test the tps sensor by turning the butterly while probing

topless318 · 01-23-2006, 10:42 AM

CPTON
yes my car runs. I did not drive it out of the driveway after my son brought it home but it would still idle. When I touched the gas the car would act as if it would die. I just put her in the garage.
I got my book Saturday, did the test and my vane flap door test failed. Every thing else checked out fine. Time for a new one.

Is there anyway to rebuild one of these?

Hey, I like the Bentley Manual.

CPTON · 01-23-2006, 10:55 AM

http://member.rivernet.com.au/btaylor/BMWText/technical/AirflowMeterCalibrat.html

i found this article, im trying to mess around with it right now

my check engine light would come on sometimes while driving (o2 sensor) and then the light would go out after a minute. im thinking i dont have a problem with the o2 sensor its just the afm giving it wrong readings.

I wonder if its best to get a new afm or find a used one.

CPTON · 01-23-2006, 05:38 PM

just took my car for a drive after having it park for a few months cause of a wheel bearing.

Was running well but came to a stop light and the car wanted to stall unless i kept reving it with the gas pedal. Then came to another light and the car was fine idled and everything. Got home and it was fine.

Jeron · Jeron's Garage

Sounds like hte ICV (idle control valve) we have discussed it several times on the E36 and M3 board

Rough idle at startup