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Miss Firing above 30 - 40% Throttle??

NA_R33

By NA_R33,
in General Automotive Discussion

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NA_R33 Grand Master

NA_R33

Posted
Posted

Hey all,

Just a quick question, my car started miss firing the other day above 30-40% throttle and generall high in the rev range, then it went away. Came back today just before i filled it up but alot worse like doing 100% of the time newhere above like 20% throttle. The plugs are only 5000k's old so im asuming its not them could it be bad fuel as it went away again about 10 mins after filling it up?? I just though bad fuel would only effect highly tuned cars, mine only has an safc and slightly advanced timing? Nehelp?

Cheers

John

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Tosh Grand Master

Tosh

Posted
Posted

I had a very similar issue with my car (MR2 Turbo)

First of all after changing the alarm system the problem went away for approx 6 months. (the wiring on the old alarm was dodgy with a capital CRAP!) However the miss did return after that and ended up being the fact that the distributor and rotor button were worn out and hence the engine was not getting spark causing it to miss fire and sound like it was running on 3 cylinders.

For you car I would reccomend checking out the coils to make sure youre getting enough spark & check the plugs to make sure they're not fouled.

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