07-12-2005, 12:25 PM | #11 |
The Kocky One
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Re: Some mis-firing input please....
The MAF you swapped with - was it a known working MAF off a working car? If not, it does indeed sound like classic MAF issues.
Any detonation occuring at the same time?
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07-12-2005, 12:43 PM | #12 |
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Re: Some mis-firing input please....
Not really detonating. Just sputtering EXACTLY like timing or a vacuum leak. The MAF was a stocker from a working car. Checking into the vacuum & distributor today.
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07-12-2005, 12:48 PM | #13 |
The Kocky One
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Re: Some mis-firing input please....
In that case, I'm leaning towards a vacuum leak as well...
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07-12-2005, 02:37 PM | #14 |
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Re: Some mis-firing input please....
A vacuum leak will usually show up at idle as well, and cause a rough/missing idle.
Try something else. Get it to misfire/bobble like normal, then put it into open loop and see if it still exists. Easiest way to do that is just go WOT when it's happening. |
07-12-2005, 04:04 PM | #15 |
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Re: Some mis-firing input please....
[Quote=Coupe]
Give it more gas (ie: roll into it hard) and it is not noticable... Still a bobble/sputter up to 2400...unless you're about 1/2 throttle or better.[/Coupe] Sounds like he has already done that which is why I suspected vacuum leak...there is no vacuum at WOT.
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07-12-2005, 05:56 PM | #16 | |
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Re: Some mis-firing input please....
Quote:
However, I'm sure it is unlikely to be noticable since a vacuum leak is usally very small compared to the 58+mm opening into the intake.
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07-12-2005, 09:16 PM | #17 |
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Re: Some mis-firing input please....
If it goes away at open loop then I wold suspect something in the 02 sensors or harness.
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07-12-2005, 09:31 PM | #18 | |
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Re: Some mis-firing input please....
Quote:
My point was also that the small leak compared to the TB will be negligible at WOT.
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07-13-2005, 05:28 AM | #19 | ||
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Re: Some mis-firing input please....
Quote:
Quote:
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07-13-2005, 07:29 AM | #20 |
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Re: Some mis-firing input please....
Found a bad ground for the MSD-type (other brand) ignition...STILL didn't fix it! I replaced distributor with a known working piece...Still didn't fix it. Cannot find vacuum leak; it's a cobra intake with only a small vacuum tree under the plenum. Seems to be fine. The 2400 RPM thing has made me think the ignition box...but the stock ignition does not fix anything. Overall; changing these things has slightly improved the problem...but not repaired it...I'm thinking O2 now...
Or maybe plug gap??? Checking it next.
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