So, it idles on 3 cylinders - why?
#1
So, it idles on 3 cylinders - why?
This actually started quite some months ago and I never bothered to look into it. This is one of my winter projects and I'm looking for input.
Car starts and idles on 3 cylinders. Cold worse than hot, but still. I noticed this due to shaking engine and less vacuum.
Seems back to normal above 3000rpm-ish. Power is there: 235rwhp.
Cylinder 3 is not doing much. I can pull the plug wire and it idles the same. Not so on other cylinders.
Swapped injector, same.
Swapped coil between 2 & 3 (same pack), same.
Plug wire sparks violently on block if I let it. Less on other plugs actually so plenty of spark.
So - what are the options we have left?
- faulty or leaking HLA
- ?
I will have compression and leak down tested soon, but want ideas now.
Car starts and idles on 3 cylinders. Cold worse than hot, but still. I noticed this due to shaking engine and less vacuum.
Seems back to normal above 3000rpm-ish. Power is there: 235rwhp.
Cylinder 3 is not doing much. I can pull the plug wire and it idles the same. Not so on other cylinders.
Swapped injector, same.
Swapped coil between 2 & 3 (same pack), same.
Plug wire sparks violently on block if I let it. Less on other plugs actually so plenty of spark.
So - what are the options we have left?
- faulty or leaking HLA
- ?
I will have compression and leak down tested soon, but want ideas now.
#6
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I say look into the valvetrin, really the only other thing left since you have ruled out fuel and spark. Probably pointless even if you haven't already done it BUT..try swapping plug wires..? Good luck.
EDIT: nothing wrong with the injector's harness (car side not injector side) on #3 is there?
#9
Probably pointless even if you haven't already done it BUT..try swapping plug wires..? Good luck.
EDIT: nothing wrong with the injector's harness (car side not injector side) on #3 is there?
#10
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Probably not, but you never know, could be a fray in a wire or something and when the engine is at higher rpms it makes better contact **shrug** w/o testing the valve train that's the only thing left that comes to mind
#14
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I still made 230rwhp as I blew my motor on the dyno itself. Ever since May I had smoke in boost and bad blow by. I had good compression across the board but horrible consumption. When I finally swapped the shortblock I only drained 3/4qt of oil, maybe 300 miles on it since the last change. lolz.
#15
I still made 230rwhp as I blew my motor on the dyno itself. Ever since May I had smoke in boost and bad blow by. I had good compression across the board but horrible consumption. When I finally swapped the shortblock I only drained 3/4qt of oil, maybe 300 miles on it since the last change. lolz.