Just did plugs/wires.. now misfire at idle.. what am i doing wrong?
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The car is a '98 Z28 w/ 86k miles... it had the original plugs and wires..
the old plugs that came out had a gap of .070
the factory spec is .060 and the plugs that went in are the ngk tr55's.. they all seem to be gapped to around .050-055
after starting it up again, there's a slight miss at idle.. my friends hp tuner says there's misses in 3,4,5 cylinders... not enough to throw a code. but enough to run like doo doo at idle but it clears up at higher rpm's
should i regap the ngk's to 70 or should i put the stock ones back in?
and is there anything else i should be checking?
the old plugs that came out had a gap of .070
the factory spec is .060 and the plugs that went in are the ngk tr55's.. they all seem to be gapped to around .050-055
after starting it up again, there's a slight miss at idle.. my friends hp tuner says there's misses in 3,4,5 cylinders... not enough to throw a code. but enough to run like doo doo at idle but it clears up at higher rpm's
should i regap the ngk's to 70 or should i put the stock ones back in?
and is there anything else i should be checking?
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well kinda pull on them a little see if you find one that just wants to slip off I know the one on the pass side rear is a SOB to get at. But I'm telling you that thier is no reason that that gap you have is going to cause a missfire. But I could be wrong I dont know much about those plugs seems like alot of people have them and recomend them though.
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Try changing back to your old wires to see if there's some problem with the wires. Check the ohmic reading for the new wires (and check the old ones while you're at it). Label the wires with a piece of masking tape (1 through 8) so you can keep up with what's what. Then you could also switch back to the old plugs in 3, 4 and 5 just to troubleshoot.
Steve
Steve
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well that's strange.. miss was in cyl 3,4,5 .... i put the stock plugs back in just those 3 cylinders and she runs like a dream again. i guess it didn't like the NGK's
what possible reason would there be for only 3 cylinders running like crap with ngk's gapped at .055
what possible reason would there be for only 3 cylinders running like crap with ngk's gapped at .055
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I had one plug wire this year that kept slipping off of the spark plug!
The damn thing clicked on each time just fine, but a slight pull, and the wire fell off into my hands.
Even when I tested this wire on an old plug (outside the car) sure enough, it just didnt catch or latch. I swapped out the wire with a new one (i jave spares), it clicked in and stuck just fine.
The damn thing clicked on each time just fine, but a slight pull, and the wire fell off into my hands.
Even when I tested this wire on an old plug (outside the car) sure enough, it just didnt catch or latch. I swapped out the wire with a new one (i jave spares), it clicked in and stuck just fine.
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yup 2 clicks.. that wasn't the issue. 3 of the 8 plugs i got from summit seemed to be bad, since swapping in the old plugs in the cylinders with the miss cleared it up
how could a new spark plug be bad? the gaps were fine
how could a new spark plug be bad? the gaps were fine