2000 Express no spark

[mopar95]

2000 Chevy Express. 5.7 350. This thing has been a headache since it came in. It would start and run for 2-3 minutes then stall. Start again, stall again. It would do this 3 times then not start for a few hours. It did this 4 times and now won't start at all. No spark. It was throwing a crank sensor code PO336.

What's been done/checked:
New crank sensor. (changed 2 times)
Still no spark
Ignition control module tested good
Coil tested good
Pickup coil/cam sensor tested along side a new one. Good.
New ECM pre-flashed from Autozone. Should at least try to start

Still no spark. But I finally was able to pull a code. PO336, crank sensor again. Changed it for the 3rd time. Still no spark.

A couple things that I have noticed:
The check engine light stays on. Normally it would go out after a few seconds. This stays lit. The other thing, the fuel pump runs when you first key on. No matter how many times you crank, it won't come back on until you key off. Key back on and the pump runs again.

Also, I am testing for spark at the coil. This way I eliminate the possibility of a bad cap/rotor. I have been able to test the wiring, as much as possible without a schematic. The yellow signal wire from crank sensor should carry a 5+ volt to ECM for signal to spark. It's not getting any voltage out. The crank sensor has a good ground and a 12+ key on. Same is true for the Icm. Up to the point that I changed the ECM, the coil also did. Now I have a key on 12+ on both sides of the coil. One should be a negative signal wire to spark that comes from the ICM.

If I have missed any info, please let me know. I am in dire need if some help before I just wipe my hands of this van.

[MT-2500]

Originally Posted by mopar95

2000 Chevy Express. 5.7 350. This thing has been a headache since it came in. It would start and run for 2-3 minutes then stall. Start again, stall again. It would do this 3 times then not start for a few hours. It did this 4 times and now won't start at all. No spark. It was throwing a crank sensor code PO336.

What's been done/checked:
New crank sensor. (changed 2 times)
Still no spark
Ignition control module tested good
Coil tested good
Pickup coil/cam sensor tested along side a new one. Good.
New ECM pre-flashed from Autozone. Should at least try to start

Still no spark. But I finally was able to pull a code. PO336, crank sensor again. Changed it for the 3rd time. Still no spark.

A couple things that I have noticed:
The check engine light stays on. Normally it would go out after a few seconds. This stays lit. The other thing, the fuel pump runs when you first key on. No matter how many times you crank, it won't come back on until you key off. Key back on and the pump runs again.

Also, I am testing for spark at the coil. This way I eliminate the possibility of a bad cap/rotor. I have been able to test the wiring, as much as possible without a schematic. The yellow signal wire from crank sensor should carry a 5+ volt to ECM for signal to spark. It's not getting any voltage out. The crank sensor has a good ground and a 12+ key on. Same is true for the Icm. Up to the point that I changed the ECM, the coil also did. Now I have a key on 12+ on both sides of the coil. One should be a negative signal wire to spark that comes from the ICM.

If I have missed any info, please let me know. I am in dire need if some help before I just wipe my hands of this van.

You might want to ceck ign switch and wiring to crank shaft sensor and other ign parts.

[thommy]

Originally Posted by mopar95

2000 Chevy Express. 5.7 350. This thing has been a headache since it came in. It would start and run for 2-3 minutes then stall. Start again, stall again. It would do this 3 times then not start for a few hours. It did this 4 times and now won't start at all. No spark. It was throwing a crank sensor code PO336.

What's been done/checked:
New crank sensor. (changed 2 times)
Still no spark
Ignition control module tested good
Coil tested good
Pickup coil/cam sensor tested along side a new one. Good.
New ECM pre-flashed from Autozone. Should at least try to start

Still no spark. But I finally was able to pull a code. PO336, crank sensor again. Changed it for the 3rd time. Still no spark.

A couple things that I have noticed:
The check engine light stays on. Normally it would go out after a few seconds. This stays lit. The other thing, the fuel pump runs when you first key on. No matter how many times you crank, it won't come back on until you key off. Key back on and the pump runs again.

Also, I am testing for spark at the coil. This way I eliminate the possibility of a bad cap/rotor. I have been able to test the wiring, as much as possible without a schematic. The yellow signal wire from crank sensor should carry a 5+ volt to ECM for signal to spark. It's not getting any voltage out. The crank sensor has a good ground and a 12+ key on. Same is true for the Icm. Up to the point that I changed the ECM, the coil also did. Now I have a key on 12+ on both sides of the coil. One should be a negative signal wire to spark that comes from the ICM.

If I have missed any info, please let me know. I am in dire need if some help before I just wipe my hands of this van.

Is this van fixed yet?

[Jakevolmer]

Im having the same issue. I even ordered a new ecm and programmed it and still doesnt get a spark. Did you ever get the van running?

[aleekat]

Originally Posted by Jakevolmer

Im having the same issue. I even ordered a new ecm and programmed it and still doesnt get a spark. Did you ever get the van running?

His last post was 5 yrs ago.

But this sounds like a security issue. Is your security light on?

[Jakevolmer]

No. I had that problem before but thats not it. It just shut off while i was driving and now wont start