1990 325is - 153 ecu
As the title states, about six months ago I was just pulling into the driveway after returning from town and the car started idling very roughly; ~600 rpms if even, motor became very shaky, bad miss, no thottle response, all before it eventually shut itself off whether you gave it throttle or not. After a couple more shaky starts and repeated results it ceased to start altogether. It would however turn over but not start.
Video of rough starting and idle leading to the no start issue. old motor
I had another built M20 at the time ready to swap in along with a new ignition system (plugs, wires, cap, rotor, and coil), new alternator and starter, new fuel pump and filter, pink top injectors, fuel regulator, new rubber boots and vac. lines, and air filter; about everything has been replaced besides the factory harness and ecu.
Now on to what diagnosing I have done. I know I have spark because the car will start with ether and run for a couple brief moments before shutting off again. That should also mean I am getting signal from the CPS. I know the injectors are not firing when the starter engages because I pulled the rail off and placed a paper towel over the injectors and I saw no moisture and smelled no fuel. I am however getting plenty of fuel to the rail. I tested the main ecu harness connector as instructed by RTSauto.com for continuity throughout the harness as well as to ensure all sensors are correctly functioning and everything seemed to check out, including the two injector bank circuits which do engage and I can audibly here the injectors "click" when I ground them. The C191 injector harness connector also tested good for continuity. I also ensured no fuses were blown.
Im not left with too much besides a faulty ECU, which I have a functioning unit on the way. I should probably replace the engine bay relays, but for the meantime i'm sure they are functioning. Anyone else have any ideas if for some reason this isn't it?
As the title states, about six months ago I was just pulling into the driveway after returning from town and the car started idling very roughly; ~600 rpms if even, motor became very shaky, bad miss, no thottle response, all before it eventually shut itself off whether you gave it throttle or not. After a couple more shaky starts and repeated results it ceased to start altogether. It would however turn over but not start.
Video of rough starting and idle leading to the no start issue. old motor
I had another built M20 at the time ready to swap in along with a new ignition system (plugs, wires, cap, rotor, and coil), new alternator and starter, new fuel pump and filter, pink top injectors, fuel regulator, new rubber boots and vac. lines, and air filter; about everything has been replaced besides the factory harness and ecu.
Now on to what diagnosing I have done. I know I have spark because the car will start with ether and run for a couple brief moments before shutting off again. That should also mean I am getting signal from the CPS. I know the injectors are not firing when the starter engages because I pulled the rail off and placed a paper towel over the injectors and I saw no moisture and smelled no fuel. I am however getting plenty of fuel to the rail. I tested the main ecu harness connector as instructed by RTSauto.com for continuity throughout the harness as well as to ensure all sensors are correctly functioning and everything seemed to check out, including the two injector bank circuits which do engage and I can audibly here the injectors "click" when I ground them. The C191 injector harness connector also tested good for continuity. I also ensured no fuses were blown.
Im not left with too much besides a faulty ECU, which I have a functioning unit on the way. I should probably replace the engine bay relays, but for the meantime i'm sure they are functioning. Anyone else have any ideas if for some reason this isn't it?
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