Hi,
I have a 96 850 that had a bad MAF (hard starting/running, throwing code P0103). I got a Cardone rebuilt unit and installed it and reset the CEL. The new unit ran fine for about 1 day, then I got a CEL again. This time it's P0102.
My question is, what voltages should I expect to see from the MAF? I have an OBDII monitor where I can watch the air intake in real time and I see the voltage changing as I increase RPM's so I don't know what could be wrong with the new sensor since I don't know what I should see for output from this unit.
Any ideas?
Thank you.

Ignition on (but engine not) .1-.2 V.. Idling should be about .9V. Should go up as speed goes up...

To check, first make sure the intake air hoses are not cracked.. Then engine off/key in ignition check pin 3 vs the ground. It should be battery voltage. If not theres your problem. Pin three is the 2nd from the left when looking at the pins (ie, you're the MAF and the wires are going into you.. 2nd from left). If OK then turn the car off, and wait 5 minutes, then check pin 4 (far left same viewpoint) for resistance. It should have 9-11K Ohms, if other report back. If OK ignition on (engine off) again, and check voltage between pins 2 and 4. Should be .1-.2V if OK, I'd try a new MAF.
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If you're not driving it "like its stolen," are you really driving?

Hi,
I checked the voltages at the connector, with the connector removed. I saw +12 on pin 3 (third from left looking into the connector). Pin 4 had 9k to ground.
As for the voltage across pins 2 and 4, I assume you mean with the connector connected to the MAF, is that correct? There's no voltage there with the connector off and the ignition on (engine off).
Thank you.

Yes, check 2 and 4 with it connected to the MAF, ignition on engine off. You can also try engine on and see if you get .9V (or thereabouts).

You have verified that your air intake hose (between throttle body and MAF) isn't cracked and is tightly connected, correct?
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If you're not driving it "like its stolen," are you really driving?

I checked all the hoses and they are fine.
I replaced the MAF with another rebuilt one and this one appears to be working fine, as I have not gotten a CE light yet. Fingers crossed.

Thank you for your help.

Regards,
Bob

I just wanted to make sure we had narrowed it down. Odds are you'll be fine, I'm guessing they just did a bad job rebuilding it.
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If you're not driving it "like its stolen," are you really driving?

Interesting, is this a turbo or non-turbo? They use different MAFs. When you installed the MAF, is the arrow flowing toward the throttle body? Did you use electrical cleaner on the electrical plug? Is the plug zip tied to the air cleaner like it is supposed to be? You never touched the sensor while installing?

Are there any another problems?

Klaus
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Always willing to listen, just not able to take direction.

Thank you for the replies.

It's not a turbo. I did check the connector contacts and they looked clean. I inserted/removed the connector about 10x to wipe the contacts. As far as I can tell, the MAF unit can only go on one way with the o-ring side into the air cleaner box, and yes, the arrow goes towards the throttle. I did not touch the sensor since it's inside the new MAF housing. There's no other issues with the car. The connector was not zip tied to the air cleaner.

Regarding the part number, I checked the Cardone site and they do not offer a separate part for the turbo vs non-turbo. I got the 74-10044. If they are indeed different, that would explain it. Also the FCP site shows the same part for both models.

I'll check the voltages and resistance as recommended and report back.