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Old 09-17-2016, 05:53 PM   #1
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Default MAF Sensor Issue

Hi all,

I've been hunting an issue where the car will just not idle without stepping on the accelerator, feels like it's misfiring, huge loss in power, very rich exhaust smell, etc. After replacing a few parts, I tried unplugging the MAF sensor, and the car runs/idles just fine. Hopefully someone may have more insight.

Here is an example with the MAF sensor plugged in. The times you see the revs go up are when I tap the accelerator. It will die if I don't tap the accelerator.

And here it is with the MAF sensor unplugged:

Parts I have replaced:
-Coil Pack
-Oxygen Sensor
-ECU Coolant Temp Sensor

Grounds I have checked:
-Rear of intake manifold
-Above alternator
-Strap to the left of the brake booster
-5 pin ground to the right of the brake booster

The car is a stock 1994. This issue occurs with both MAF sensors I have tried. The MAF sensor is getting 12v at the plug, not sure what else I can measure. Any help in resolving this will be greatly appreciated.

Last edited by Cococarbine3; 09-17-2016 at 06:03 PM.
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Old 09-17-2016, 07:56 PM   #2
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Have you ever adjusted the throttle valve open/closed from the factory setting? It may not be opened up enough to idle at the proper RPM. I would look up how to properly set the idle on your car, and do that.
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Old 09-17-2016, 08:53 PM   #3
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After a long search, I have found and resolved the issue. The crack in the IAC air hose was facing to the ground and unnoticeable unless you were looking for it specifically. All is well now.

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