Hello everyone - I searched the threads and found similar problems mentioned, but this one is really confusing me.

No voltage to green/orange coil primary except during initial relay cycle. When cranking, nothing. This would indicate a cam or crank sensor not sending a signal to the PCM, right? Well, I replaced both...also put in a reman PCM (twice just to be sure). Good supply voltage to both sensors, good solid grounds also. Again.....supply voltage to coil primary only during initial ASD relay key-on cycle, none after.

Please help....I've been at this so long I can't diagnose anymore. I need a few fresh minds working on it. Thanks..............Chris

 

Check and see if the PCM is actually tripping the relay while cranking. If the PCM doesn't see the engine turning via either the cam, or crank sensor, it won't turn on the ASD relay. Apparently, that part of the system (ASD) is working... as you get momentary power to the coil.

What about the injectors? Got power there at all? (initially, and while cranking.)

 

Agreed, thanks. That's what I'm thinking....but I don't know if the PCM is receiving the signal from the sensors or not. After all the new stuff, it's confusing.

With key on, if I tap the crank sensor on an engine ground, the ASD should click - it doesn't. I've always had the suspicion that another component is preventing the PCM from triggering the gree/orange that goes to coil, injectors, and other stuff. I seem to be getting good 8v and 5v supply to the various components.

Thanks

 

Check connectors at the PCM, sometimes they like to corrode up, and stop working right.

 

Yea - I guess I was checking that as you were replying! I took off the PCM connector and slid out the small red plastic retainers in the inside (of the connector, not the PCM). With the point end of a test light, I pushed on one side of each terminal split connector to close it down a bit. Plugged back in and started the engine.

Important note, boys and girls - - before disconnecting PCM, disconnect battery ground (-) cable. Reconnect PCM before reconnecting battery.

Thanks for the insight, Hey You -