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MAF airflow wire

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Old Jul 23, 2016 | 08:37 PM
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MAF airflow wire

I am I assuming right that the mass airflow burnoff black ground wire send power to the mass airflow black ground to power it? I check the black ground wire from the ECM back to the mass air flow black wire and did not get a reading. So that tell me that it is a break in the wire correct?
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Old Jul 23, 2016 | 08:49 PM
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Re: MAF airflow wire

Ground wire shouldn't have power
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Old Jul 23, 2016 | 09:02 PM
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Re: MAF airflow wire

Originally Posted by TTOP350
Ground wire shouldn't have power
It does not have power. It grounds the relay so power can go to the mass airflowe relay.
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Old Jul 23, 2016 | 09:16 PM
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Re: MAF airflow wire

The 1st post is hard to understand exactly. I get what you are saying now.
What kind of reading are you looking for on the ground wire? continuity ?
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Old Jul 24, 2016 | 07:11 AM
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Re: MAF airflow wire

Originally Posted by TTOP350
The 1st post is hard to understand exactly. I get what you are saying now.
What kind of reading are you looking for on the ground wire? continuity ?
Yes continuity.
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Old Jul 24, 2016 | 07:15 AM
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Re: MAF airflow wire

If the ECM isn't closing the relay, you won't have continuity..
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Old Jul 24, 2016 | 09:00 AM
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Re: MAF airflow wire

Study the schematic. The MAF signal ground ("B" terminal) connects to the ECM. The MAF power ground ("A" terminal) connects to a chassis ground.
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Old Jul 24, 2016 | 09:35 AM
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Re: MAF airflow wire

Vader I pulled the ECM harness and the MAF harness. I probe the black wire on the MAF wire harness and the black wire on D12 from the ECM harness. I set my DVOM to continunity where it beeps to see if there was a break in the wire. I did not get a beep so I am thinking there is a break in the black wire. I am on the right track? Thanks for everyone help. I will get it straight soon.
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Old Jul 24, 2016 | 11:11 AM
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Re: MAF airflow wire

The black wire ("B" terminal) should have continuity from the MAF connector to the ECM connector (D12). You may have discovered a problem. I don't believe there are any other connectors in the circuit aside from those two.
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Old Jul 24, 2016 | 11:49 AM
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Re: MAF airflow wire

Vader yes that is what I am talking about. There is no continuity from the black wire ("B" terminal from the MAF connector to the ECM connector (D12). So is that is a break in the wire?
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Old Jul 26, 2016 | 05:11 AM
  #11  
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Re: MAF airflow wire

UPDATE: TTop and Vader thanks for all of your help. I replaced the black wire from the mass airflow harness to the ECM wire. Turns out that help with my hunting idling issue. I am still getting the code 33 and 41. I will address those one on one.
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Old Jul 31, 2016 | 10:20 AM
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Re: MAF airflow wire

When I was having MAF code issues I came across a hard to diagnose issues. I had all the power and continuity I should have, tried a different sensor etc. In the end my issue wound up being the connector at the MAF. The pins had been widened, probably from years of removal and reinstall. The springy parts of the contacts were not contacting the pins on the sensor any longer. A small pick and some tweaking on those on the connector itself and everything was good to go again. Just something worth checking.
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Old Jul 31, 2016 | 04:32 PM
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Car: 1989-92 FORMULA350 305 92 Hawkclone
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Transmission: 700R4 4800 vig 18th700R4 t56 ZF6 T5
Axle/Gears: 3.70 9"ford alum chunk,dana44,9bolt
Re: MAF airflow wire

Originally Posted by ViperSpec
When I was having MAF code issues I came across a hard to diagnose issues. I had all the power and continuity I should have, tried a different sensor etc. In the end my issue wound up being the connector at the MAF. The pins had been widened, probably from years of removal and reinstall. The springy parts of the contacts were not contacting the pins on the sensor any longer. A small pick and some tweaking on those on the connector itself and everything was good to go again. Just something worth checking.
Very good tip right here, I had to do the same thing myself.
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