porsche 931 backfiring

[ozporsche]

i have a weird problem with my 1980 924 turbo, it starts fine from cold start, then it has a slight miss, if you rev it quickly it backfires, if you accelerate slowly it revs fine right up to hi revs, if you load it up whilst driving, it stalls, then wont restart, then you see fuel coming out of the exhaust from cyl 1. on idle the car runs fine, i have checked timing, leads, plugs (all new) dizzy cap and rotor button also new and correct ones for car, fuel pumps ok and fuel mpump relay ok, checked all earthing and seems ok.

could anyone help ???

[wvicary]

Sounds like a lean condition and If you have fuel coming from one cylinder then the injector might have a problem. The CIS injectors should open at approx 42-48 psi but they can leak,open under lower pressure and have very poor spray patterns which will affect the volume of fuel to the remaining injectors. You need to put a pressure gauge on it and see whats going on.