Missing like a Fook!

[clawsk]

My gsi has develpoed a misfire, sounds just like an scooby! It has lost abit of power but not loads, have replaced the ignition system, and give it a service but still no luck. Im thinkin its overfueling and tryed playin round with the co2 screw on the jetronic this morning and it helped a bit.

How do i alter the fueling on the gsi?

Is there anythin else that could cause a miss fire?

I dont think its dropped a valve cos it will still do a tonne 10 on the by pass.

Cheers for any help 8)

[Jules]

First thing to do is to get it to a garage and have a compression test done - I had the same problem with my GSi and it turned out that only 1 piston had all it's rings intact and the rings on one of the pistons were so messed up that it had damaged the piston and had to be replaced - 1 new piston and a whole new set of rings, and of course new head gasket etc etc.
Get it tested and go from there, could be piston rings, could be head gasket, could be a knackered sparkplug or a blocked injector - but make sure the compressions on the cylinders are ok before spending money on bits that may not be faulty.

[robb]

Sounds unlikley but check you haven't taken out a rocker.

[Stuart]

cam timing is likely to be the suspect here

as for adjusting the fuelling with an ecu controlled enigne, good luck unless its mappable lol

the co screw is only for adjusting the minor emission