Car is a 95 Legacy 2.2GX

Stopped as normal in drive - refused to start again - backfired heavily

To cut a very long story short we discovered the timing belt had jumped 4 teeth (it's happened before - design fault but that's another story!) we've replaced the MAF unit which stopped it from backfiring on cranking (replaced the old MAF and backfiring resumed)
Towed it to a dealer who read the error codes and said the Cam sensor was down - replaced it on the basis the car would now start - it doesn't!
There is petrol getting through and the Cat has not collapsed.

Upon investigation the spark appears to be on time at cylinders 3 & 4 but there are at least 4 sparks appearing on cylinders 1 & 2

Is my ECU knackered??

ALL IDEAS GRATEFULLY RECEIVED!!

thanks

 

coil packs...???

Dan

 

we had a 2.2 that was stopped on the drive and left for 5 weeks it would then not start the only thing we did was to replace the crank sensor which then allowed it to atart. the strange thing was we then put the old sensor back on and it still started.We left it with the old sensor and it is still going strong. If you have tried the crank sensor and you do find something else let me know.

 

Doesn't appear to be the coil packs - have reversed the LT input to the coils and the problem swaps to the other 2 pots

Something appears to be telling it to spark 4 times per rev!!

 

Got her started and running like a dream again

Basically it was the crank sensor giving unreliable data!!
Will fill you in with the details when we've worked them out!!

Thanks for your help guys!

PS - This is a legacy that is running on LPG and has been for the last 50k miles - now got 125k on - didn't mention it before because we were convinced it was not relevant (and we were right on that at least!!) Runs great and is 37ppl - about 4.5 mpl