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Hi Guys,

I've searched and had a thread in general maint. with no luck so here goes:

I currently have a slight miss on idle. Car is a stagea series one (pre Neo engine).

Its only ever so slight that you must concentrate very hard on the tacho to notice it at all, best way to tell when its happening is to stand next to the exhaust when its idling and listen for the slight change in exhaust tone for a split second. Looking at a digital RPM read out it drops only about 30rpm when it does it.

So far I have done this:

Pulled all plugs and checked them and coil packs (Splitfires)

Pressurised intake system to check for leaks with no signs except rocker cover gaskets

Replaced rocker cover gaskets and halfmoons

Cleaned airflow meter

Cleaned throttle body

Checked 02 Voltages on Consult

What else could it be? Could it just be running really rich?

Ive only really noticed it since Ive put a manual gearbox in it.

What else should I try, I was thinking maybe clean the AAC valve again (did it only a few months ago), replace the plugs even though the current ones have only done 2,500k's?

Car runs fine elsewhere except for some form of cut either boos fuel or rich and retard when i really load up the engine eg. full throttle up hill in a gear to high, reason i want to fix up this miss is so I can get the SITC, SAFC and EBC tuned to get rid of this cut im experiencing.

Sorry for the long post.

Cheers, Chris

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https://www.sau.com.au/forums/topic/334029-slight-miss-on-idle-rb25det/
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