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Misfiring

deesh

By deesh,
in General Automotive Discussion

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deesh Collaborator

deesh

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Posted

Anyone have any ideas why my car misfires at two times:

1) cruising from 70-100 or so, then throw it back to 3rd, and floor it, i get a pause, about 3 small pops, and it takes off like a rocket. This is not so bad, just a bit annoying.

2) Taking a slow corner, or almost stop at lights or something, 2nd gear, low revs, if i give it too much too soon, i get almost full boost, but the revs wont pick up, it feels as if its choking, sometimes it misfires. I have to back off, let the pressure blow of, pick up the revs a bit, then floor it.

I have a SAFC, i dont think its fuel. The car has done this for as long as ive had it, im just getting sick of it.

Someone suggested spark, and pulling the plugs out, cleaning and gapping to 0.8 has made it a bit better. I have NGK plugs, any suggestions, new plugs (what brand), or other causes?

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Gradenko Mentor

Gradenko

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It sounds like not enuf spark is getting through for one reason or another. Could be coil packs playing up, heres a cleaning technique I read in HPI (or was it Zoom?):

- clean the rubber boot on the coil pack with degreaser. Dirt and grime makes it easier for spark to find ground through the insulating boot rather than the spark plug

- spray the rubber boot with a silicon based spray to further insalate it. (I used WD40)

If none of the coil packs are terminaly fautly, hopefully that should sort it out.

NGK plugs are safest to use with our cars, they come factory standard on all jap cars I've seen. Whats the service interval for NGK coppers, 10-20k km? Probably best to replace them if you don't know when they were last changed.

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deesh Collaborator

deesh

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Posted

yep, they are about 6000 k's old. There was some oil around the coil packs, which looked like it was clean, and put there intentionally, ill try WD40 or something. The coil packs actually look quite new.

I am going to get those expensive plugs, to see if it makes a difference, seings its only under high load, that it misses.

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