Hello everyone, I’ve got a 94 3.0 manual that was running rough on the day that it wouldn’t start. I was going to the store and at stoplights, the truck would die on me. I would have to turn the truck back on at every light that particular day, and I kept it running at stops by giving it a bit of throttle.

When I parked and stopped at the store, that’s when the truck would no longer start. (I saw the spark/coil pack at the very top of the engine smoke a little bit upon checking under the hood)

Now, all I hear is one singular click when I turn the key. I started with the battery and it check out good (12.83 V), swapped out the starter solenoid attached near the driver side (still a singular click), and finally I replaced the starter motor (still hear a singular click, but this starter is at least able to make the pulleys twitch when it attempts to crank). Also jumping the solenoid produces this same effect with the singular click.

I decided to read the OBD1 KOEO codes and I would get 512 & 513 which points to an issue with the PCM. I assumed this was maybe just occurring due to me leaving the battery disconnected and reconnected for a good bit of times while diagnosing. Either way, I pulled out the PCM and checked the connectors for corrosion, checked the pins for corrosion, and I checked the board inside for any blown capacitors etc. however it all looked to be in great condition.

I just wanted to know if anyone had any thoughts on where I could diagnose next since I am currently stumped in my diagnosis. Thanks!

 

could the motor be froze up? can you rotate the crank pulley by hand?

 

Sadly this morning I tried rotating the crank by hand with a breaker and it did not turn. I also made sure to do so with the spark plugs removed. I’m guessing it’s seized up then?

 

Was the serpentine belt on or off? There could be a chance something was locked up and not the motor, good luck!

 

Serpentine belt was left on. Should I try to crank it by hand with the serpentine belt off? Thanks for following up!

 

I would. There’s a chance, so cross your fingers that it’s something else besides the motor. I suppose the motor would wiggle just a little bit one way or the other if it was the water pump alternator or air conditioner but who knows. I have seized a few motors. They are usually out of oil or water, and have heated up or something breaks and you can hear it. This doesn’t seem to be your case?