I was coming home from 1 1/2 hr. drive Friday when out of the blue my '87 325 (M20B25) acted like the the ignition switch was turned off, it just stopped running. I pulled over, and tried to restart it, it would crank but not start. After getting the car home, I checked in the following order:
Cam was turning when cranked (OK),
Main Relay (OK),
Fuel pump pressure (OK),
Spark (No Spark),
Spark from primary coil wire (No Spark),
Power getting to coil (OK),
CPS (OK),
Pulled the ECU connector and checked the Power, Grounds and all other values (All OK),
Replaced the ECU, it tried to crank on the first try, got it started, took it for a drive. Hooked up the old ECU again, no start.
When you have fuel but no spark, sometimes it "is" the ECU!
Cam was turning when cranked (OK),
Main Relay (OK),
Fuel pump pressure (OK),
Spark (No Spark),
Spark from primary coil wire (No Spark),
Power getting to coil (OK),
CPS (OK),
Pulled the ECU connector and checked the Power, Grounds and all other values (All OK),
Replaced the ECU, it tried to crank on the first try, got it started, took it for a drive. Hooked up the old ECU again, no start.
When you have fuel but no spark, sometimes it "is" the ECU!
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