Low Ignition Coil HT Lead Resistance. Engine Misfiring

jackocooper
Fri, 08 Sep 2017 07:26:40 +0000
Maintenance/Repairs

Hi, I have a 1988 Alfa Romeo 75 (Milano) 3.0 V6 and the engine is misfiring. It sometimes cuts out at idle and has no power on acceleration. It sometimes backfires under full throttle.
Pulling out the spark plugs one by one, cylinder 1 has no effect on the engine (but spark is firing).
All fuel injectors are firing, brand new spark plugs, new fuel pump & filter.

I am running out of ideas. Testing the resistance of all the spark plug HT leads, they all have a resistance of 25k, however the lead from ignition coil to distributor has a resistance of just 1k. It is also a little corroded inside (stripped it to make better contact at coil end).
Could this be the cause of the misfire and poor running? If not, any other ideas?

Thanks for your help!
Regards,
Jack

46 posts - 12 participants