Thread: Misfire under load, increase with engine warmth and run time

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  1. #1 Re: Misfire under load, increase with engine warmth and run time 
    GrandPrix Junkie
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    There is also a specified MAF cleaning spray from CRC. I've used this on multiple cars and have never had an issue and it avoids touching the MAF wires with anything. Just spray it down, let it dry and reinstall.
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  2. #2 Re: Misfire under load, increase with engine warmth and run time 
    SE Level Member LouF's Avatar
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    I know its late, and I'm not (or ever was) expert, but the open-loop control jumps out to me on this.

    I am now big on being very sure about vacuum leaks (because of age), but this is not how it reacts when it is vacuum. Two vacuum spots you may have missed - the tee beneath the S/C snorkel and the Evap solenoid near the EGR valve (it has an O-ring inside).
    2005 Grand Prix GTP
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