#3 cylinder misfire
Posted 09-13-2016 09:45 PM
I changed; plugs, wires, coil pack.......no change
All wires are sparking......all injectors are opening (heard with stethoscope), battery has good voltage static and running.
Next step is to remove, check and clean the injectors again (did this at the beginning of the season).
This does not appear to be the usual '99 misfire issue........any ideas?
Posted 09-13-2016 09:58 PM
- Jim Drago and Jesse Prather like this
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Posted 09-14-2016 06:37 AM
Intake and or exhaust valve lash has tightened up causing a low rpm miss fire. I've seen it many times. Car idles poorly especially when cold but revs out and seems ok on track. It's not 100% on track but better than at idle. Lash tightened up because valves are pulling into head and or degrading.
I agree, leak it down
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Posted 09-14-2016 07:42 AM
I'm not an engine builder, but I agree with the 2 engine builders.
Basic engine theory is that you need 4 things to make an engine run; Air, fuel, spark, compression. Air is generally not an issue, you eliminated spark and fuel, that only leaves compression
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