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Misfire I think


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Make sure your timing correct, if you did just do a timing belt install. You could be off a tooth.

 

This is very true too. Make sure all your timing marks on the cams/crank gears line up with each other, don't trust the belt marks, trust the gear marks.

My wife's balls are delicious.
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So here's what I did. BTsSM showed mis #4. I removed plugs 2 and 4 , didn't see anything unusual. Decided to swap them since #2 is easy to get at and #4 not so much plus figured if the misfire moves I can assume freaky coil. Make the swap, start it up and no misfire showing. I let it warm up, rev it a few times and no misfire. I didn't have time to drive it but at least I have progress. All I can guess is when I installed the new plugs I somehow didn't get the #4 boot on the #4 plug correctly.
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So here's what I did. BTsSM showed mis #4. I removed plugs 2 and 4 , didn't see anything unusual. Decided to swap them since #2 is easy to get at and #4 not so much plus figured if the misfire moves I can assume freaky coil. Make the swap, start it up and no misfire showing. I let it warm up, rev it a few times and no misfire. I didn't have time to drive it but at least I have progress. All I can guess is when I installed the new plugs I somehow didn't get the #4 boot on the #4 plug correctly.
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O.K. I got to drive the car a bit with the BTsSM working. I checked the LV's 3 x 1st reading 5.7 1.2 -1.0 -2.2 2nd read 4.5 1.2 -1.0 -2.2 3rd read 4.4 1.7 1.3 -4.1 so there is something wrong somewhere. I had 5 knock events all of them between 2200 and 2500 rpm. So now I need to figure out what to look at.
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These values are not too bad actually. If these values stay within +/-5% (some say +/-8%), then you may be free of vaccum/boost leak. It is normal for them to fluctuate a bit (emphasis on *a bit*).

Did you have any learned knock values in your Timing correction table reported in the LV? Did you see zeros everywhere? And was your "IAM" equal to 1.0? If the answer is yes to the last two questions, then that is great.

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great to hear your values are all zeros and IAM is 1.0. That essentially means that the ECU has not pulled timing due to perhaps repetitive knock events at certain rpm/load ranges.

 

Now, I don't recall you answered these questions yet:

 

 

ok. How many counts are you getting?

 

Does the misfire go away when fully warmed at idle?

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It depends in what rpm/load range they occured. You want to take note of those that occured in high rpm/ high load range. But if most of them occured in low load/low rpm range, then it could be just noise and should be harmless.
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They were all 2200-2500 rpm , average acceleration. Thanks for Your help and the info on the BTsSM, that app is sweet. I'm an old school carb/NA type , My other cars are 1965 and 1970 so this Turbo is hi-tech for Me.
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No problem. I am glad you are enjoying this app.

 

If these knock events will occur again in that same rpm/load ranges, then most likely the ecu will 'learn' to pull timing in these ranges, which will show up in your LV. So pull them regularly, or put a live gauge called FLKC on your screen. If the ECU has learned to pull timing in any rpm/load ranges, this gauge will become non-zero. You can even have it make an audible sound whenever it occurs.

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Heh that's awesome. My phone wouldn't be big enough for all those. Of course the only one I understand is ambient air temp. anyway. I'll just keep trying to figure out why the car bounces at idle. I must have a tiny vacuum leak somewhere weird.
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If you want, you can try this simple vacuum leak test. Read this post: http://legacygt.com/forums/showpost.php?p=4491795&postcount=1. It describes a simple method in checking for vacuum/boost leak.

 

As for the shake, perhaps have your phone running btssm at all times with the misfire gauges, and see if a misfire shows up whenever the car shakes. I remember that's what was going on with my 05; it was misfiring just a bit but not enough to trigger the CEL. The car was shaking a bit at idle.

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