cryppie65

Almost finish with my swap, I tried to start the engine with the MAF connected it puttered like it wanted to start but no go. I disconnected the MAF and it started, all header tubes were warm with the exception of #4. #4 coil is not sparking. Does anyone have any suggestions?

cryppie65

Any suggestions???

ls1nova71

iTrader: (4)

Move the #4 coil to a different location and see if the problem follows, if it does, then replace the coil, if it doesn't, then start checking the wiring.

cryppie65

Ls1nova71, swapped coils and problem stayed on #4. Guess I will start chasing wires.

Thank you for the reply.

pdsq98gt

While you're at it check the MAF wires since it appears there is a problem with that system also. Maybe the MAF and #4 coil have the circuits crossed.

ls1nova71

iTrader: (4)

Are you sure its spark related? Could possibly be a clogged injector, that would also keep that header tube from getting warm.

cryppie65

I did some troubleshooting:

1. I swapped the coil out with a coil from another location; same problem no spark on #4.
2. I tested the Power wire to the coil; I'm getting 12V
3. I tested the chassis ground to the coil. Test Satisfactory
4. I tested the PCM ground to the coil. Test Satisfactory
5. I tested the coil trigger wire; I have a constant 5.1 volts to that wire, unlike the other coil trigger wires which show 0.1 volts
6. I checked the ignition control 2 wire for resistance and continuity. Satisfactory

Do you think my PCM may have an issue?

TomM

iTrader: (56)

Did you do what ls1nova suggested yet? No gas = no combustion = no heat.

Coil could be firing, just no fuel. Easy test is to use a screw driver the old school way and see if you get spark to the block, or some ground.

Doubt it's the PCM if it tries to start.

Who did your tune?
What MAF are you using?
What/who's harness are you using?

Swap injectors if you are getting fire to the plug. Could be that simple.

T,

cryppie65

TomM,

Thanks for the reply.

Yes, I swapped injectors and the problem is still ther. I also purchased one of those ignition tester tools to check all of the coils; all are sparking with the exception of my #4 coil. I did the harness myself and LT1Swap did my tune.

The car starts and runs but my #4 coil is not firing. I tested all of the wires and all are showing no issues that's why I was askin if it may be the PCM.

Thanks

TomM

iTrader: (56)

It could be the PCM, but typically it would have more problems than 1 specific coil. You can never rule out any possibilities. I know Chevy406 on here had a misfire issues and one of the prongs on the connector that plugs into the coils (the big gray one on the valve cover) had a bent prong and not making good contact.

In addition, I have seen the pins in the PCM connector push out from the connector body as they were not completely inserted in the connector.

I suspect you have a bad connection, or broken wire causing your problem.


T,

cryppie65

Tom,

Thanks, I'll look at the connectors to see if a prong is bent. I checked the #4 Ignition Control Wire and it checked out good.

Pop N Wood

iTrader: (1)

The MAF is supposed to have constant +5 volts to it. The coil trigger wire is supposed to pulse to trigger the spark, like you found out with the other coil wires.

Maybe the coil wire and maf power wire got swapped in the harness.