No spark
Posted: Mon Sep 15, 2014 7:09 pm
Finally pulled my '93 907 out from the back of the garage to try and get it running again. A few years back it just quit running - no spark. Tried getting it running a few times and then just decided to hang with my kids till they went off to college and/or find someone of the opposite sex to hang out with -both of which just happened so... .
Anyhow... the fuel pump wasn't priming so I troubleshot the problem down to the pump relay which was dropping 11 of the 12V across the relay contacts. I actually found a compatible relay without the 15A fuse up at the auto store for $10 which wasn't a bad price (Part No. R3177P at Advanced Auto if anyone wants to try it - all I can say right now is that it runs the pump to the priming point). So the pump now primes up but I still have the original problem of no spark.
I ohmed out the timing sensor and the rpm sensor and both are around 650m ohms.
I checked the coils and both are reading the same thing: ~1 ohm on the primary (between the contacts where the blue and green wires enter the coil) and ~3.14k ohms on the secondary (between the plug side and either contact on the primary). I checked the tech faqs and it shows a different reading so I think this may be my problem even though I find it hard to believe that I toasted both coils at the same time. Anyone have any readings that match what I see (1 ohm prim, 3.14k secondary)? Anyone know if I read the resistance at the wrong points?
Any input would be really appreciated.
Anyhow... the fuel pump wasn't priming so I troubleshot the problem down to the pump relay which was dropping 11 of the 12V across the relay contacts. I actually found a compatible relay without the 15A fuse up at the auto store for $10 which wasn't a bad price (Part No. R3177P at Advanced Auto if anyone wants to try it - all I can say right now is that it runs the pump to the priming point). So the pump now primes up but I still have the original problem of no spark.
I ohmed out the timing sensor and the rpm sensor and both are around 650m ohms.
I checked the coils and both are reading the same thing: ~1 ohm on the primary (between the contacts where the blue and green wires enter the coil) and ~3.14k ohms on the secondary (between the plug side and either contact on the primary). I checked the tech faqs and it shows a different reading so I think this may be my problem even though I find it hard to believe that I toasted both coils at the same time. Anyone have any readings that match what I see (1 ohm prim, 3.14k secondary)? Anyone know if I read the resistance at the wrong points?
Any input would be really appreciated.