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Getting baffled by a tech problem with my 2.9RS engine (93mm barrels). Basic problem appears to be all the cylinders on left hand bank aren't firing shown by really rough running at idle onwards and plug cuts on that side have no effect.

checked getting a spark and timing
checked compression, seems OK
cam timing seems OK as valve clearances were as I'd set them earlier in the year when car ran perfect,(reasoning if timing had slipped, they would all be wrong against the notches in the crank pulley)
MFI timing OK, by checking notch on pulley lines up correctly
swapped injectors around with other bank, no change

anyone any ideas as what problem could be before I get to strip the whole thing down. I'm suspicious of the MFI pump, but it was rebuilt 5years ago by a reputable agent and has been perfect to date.

Ian
 
Have you had the HT leads off the distributor? In which cases is there any chance you've got the firing order wrong, i.e. could you be sparking on the exhaust stroke?
 
Really thought I'd found the problem when we discovered the belt had slipped a notch on the pulley. Reset it correctly, fired it up again and damm me the problem was still there. Seems as though there's a huge tolerance on the injection timing!!

Can't see why the fuel pump would only fire one bank of cylinders as my understanding is that the pump's single control rack operates all cylinders fuel supply.....or is there some other logic?
 
spent the whole day strippping and cleaning everything, put all back together and it fired up perfectly..problem gone. Only thing that was a bit odd was the MFI control rack was a bit sticky so put it down to that. Thanks for the input, next time get to play in the garage will synch everything as per the check/measure/adjust manual as there's a significant difference between cylinders.
 
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