Diagnosing a no spark condition
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Joined: Jul 2011
Posts: 3
From: Missouri
Diagnosing a no spark condition
Hello all, I have a ‘96 Trans Am WS6 LT1
that I have done a 0411 PCM swap on, I drove the car with this PCM for 6 months and during the winter, driving home one night, it back fired on me and I never got it to start after that.
The tune is from a 2000 Express van 5.7,
the cam sensor has been turned off in the tune,
I tested the ICM and it was bad. Replaced it and I followed the trough the troubleshooting
steps, i have 12 volts to both the coil, and ICM.
now, my multi meter reads in millivolts, and volts. While probing the white wire while cranking, I get 1.0 volts at first, then no more than .35 to .45 millivolts.
I have continuity between pin 5 of the PCM and the white wire on the icm connector.
I also replaced the coil just in case that was bad.
is there anything else I am missing? Someone mentioned that the Crankshaft position sensor
might have to switch two leads around.
anyone see this before?
thanks!
Ben Smith
that I have done a 0411 PCM swap on, I drove the car with this PCM for 6 months and during the winter, driving home one night, it back fired on me and I never got it to start after that.
The tune is from a 2000 Express van 5.7,
the cam sensor has been turned off in the tune,
I tested the ICM and it was bad. Replaced it and I followed the trough the troubleshooting
steps, i have 12 volts to both the coil, and ICM.
now, my multi meter reads in millivolts, and volts. While probing the white wire while cranking, I get 1.0 volts at first, then no more than .35 to .45 millivolts.
I have continuity between pin 5 of the PCM and the white wire on the icm connector.
I also replaced the coil just in case that was bad.
is there anything else I am missing? Someone mentioned that the Crankshaft position sensor
might have to switch two leads around.
anyone see this before?
thanks!
Ben Smith
Registered User
Joined: Apr 2021
Posts: 31
Re: Diagnosing a no spark condition
Hello all, I have a ‘96 Trans Am WS6 LT1
that I have done a 0411 PCM swap on, I drove the car with this PCM for 6 months and during the winter, driving home one night, it back fired on me and I never got it to start after that.
The tune is from a 2000 Express van 5.7,
the cam sensor has been turned off in the tune,
I tested the ICM and it was bad. Replaced it and I followed the trough the troubleshooting
steps, i have 12 volts to both the coil, and ICM.
now, my multi meter reads in millivolts, and volts. While probing the white wire while cranking, I get 1.0 volts at first, then no more than .35 to .45 millivolts.
I have continuity between pin 5 of the PCM and the white wire on the icm connector.
I also replaced the coil just in case that was bad.
is there anything else I am missing? Someone mentioned that the Crankshaft position sensor
might have to switch two leads around.
anyone see this before?
thanks!
Ben Smith
that I have done a 0411 PCM swap on, I drove the car with this PCM for 6 months and during the winter, driving home one night, it back fired on me and I never got it to start after that.
The tune is from a 2000 Express van 5.7,
the cam sensor has been turned off in the tune,
I tested the ICM and it was bad. Replaced it and I followed the trough the troubleshooting
steps, i have 12 volts to both the coil, and ICM.
now, my multi meter reads in millivolts, and volts. While probing the white wire while cranking, I get 1.0 volts at first, then no more than .35 to .45 millivolts.
I have continuity between pin 5 of the PCM and the white wire on the icm connector.
I also replaced the coil just in case that was bad.
is there anything else I am missing? Someone mentioned that the Crankshaft position sensor
might have to switch two leads around.
anyone see this before?
thanks!
Ben Smith
Currently having the same problem as you except I have a stock PCM. Have you tested AC voltage on the white wire(pin 5 on the black connector) at the PCM? And from what I understand, the crank sensor is there to detect misfires and does not have any effect on the pulse the PCM sends to the ICM.
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97ramairtransam
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Dec 25, 2003 05:14 PM