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Surging 3000rpm


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Frankly, I'm not one for believing you can "blow out" the spark because of a bit of extra boost. When the spark is fired, the combustion space is closed (has been closed since about 55 ABDC). There may be a bit of swirl caused by the upward movement of the piston, but nearing the ignition point, the piston hardly has any vertical velocity. So I can't imagine enough turbulence to actually extinguish the spark.

A poor spark is usually a sign of a poor ignition system; closing down the gap is only a band-aid fix, and masks the true problem of a weak ignition system.

That said, 42psi at idle is too much. The handbook says 2.5 bar (36 - 37 psi) at idle, 3 bar at IGN = ON (pre-start), or at idle with FPR airfeed disconnected.

Have you replaced the coil -> spark contacts? Have you cleaned all grease and dirt off the sparkplug protectors on the coils? Have you had the injectors cleaned recently?

Open the gap back to "standard" (1.1mm).

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i havent replaced the spark plug contacts only sanded them down to be a bit smoother and flatter as they were showing pitting and burn marks,ive cleanes the spark protectors and only run injector cleaner through the petrol,im pretty sure all injectors are going as ive put a screwdriver up to them and listened and the note all sounds the same on each injector

could the blow off valve have any thing to do with the miss as it was homemade and leaked at idle

also the car seems to be running real lean could this be fuel pump not pumping enough fuel?

is there any way i can clean the injectors myself?

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