This is now my second post on this forum regarding my no-spark issue, here is a brief synopsis of what i've tried so far:
- Checked for spark with brand new plug (none)
- checked for spark coming from igniton coil (none)
- checked for voltage at igniton coil positive terminal when key is on (full voltage)
- checked resistances of coil and both crank sensors, came back good
- checked for AC voltage at crank sensor, speed sensor was a little below 4v and reference sensor was a little over 1
- replaced reference sensor because most guides suggest that the reference sensor should read a max of 0.4v when cranking, but the new sensor read the same voltage so i assume that is just a quirk of the car
- checked OBC relay, came back good
- checked main relay, came back good
- checked/cleaned all of the grounding points of the engine bay
If I have done all these tests right and gotten these results, am i correct in assuming that the only other possible reasons for me not getting a spark is because of a bad ECU or a wiring issue? if it was bad wiring, how should i go about testing it?
'85 635csi bad ecu?
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Re: '85 635csi bad ecu?
Unfortunately had to figure this issue by myself, but here is what I learned for anyone who is having the same problem; the wire going from the igntion coil to the distributor is very weak! checked every single pin on the ecu before I thought to check the continuity of that wire. goes to show that the old Motronics are very nearly indestructable, so check EVERYTHING else before the ECU.