No spark. Please help

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Druidrv

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I have an 99 trans am WS6 with no spark. Car was sitting in driveway idling and it just shut down and would not restart. I bought the pontiac service manuals and I have confirmed grounds to the coils and PCM blue pins 1 an 40. Also positive battery voiltage on blue pins 20 and 57 and ignition positive voiltage on pin 19. Grounds on the red on 1 and 40 was also confirmed. There is 12 volts to coils. All fuses and relays test ok. PCM was replaced with a known good one. Crank sensor is replaced. I have injector pulse when cranking and fuel pressure? It seems to me that the PCM is not sending the signal out to the coils. Could it be in the pass key system? If so, how do I test it? I don't know what to check next. I'm tired of seeing it just sitting there. Please help. Thanks Ron.
 
what pcm is in the car now, the original or the replacment? Installing a PCM programmed with a different VIN is only going to complicate things. Is the antitheft light on constantly?
 
It is the replacement but it has been flashed to the original vin specs. No the anti theft light goes out. I just tested the crank sensor circuit and it is good. From what the service manual reads the pass key system will not let it crank of charge with fuel. This thing cranks and fuel but no spark. We are completely out of ideas on what to do next.
 
You should be able to scan and read values , right on with the security the gives you a no crank .. I would look at the cam sensor value while cranking.
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Now I dont have any cluster lights when I turn the ignition on. Ck eng, security ,low oil, abs ect. They worked then they were gone. Is there any connection to the no spark problem? Or are these separate issues. Everything cks out and this thing should fire but no spark. Is there any thing else we can ck. I do not have the tool to do live reads of the PCM. I will have to tow it to someone for that and where we live, I have little faith on them finding a solution. They can change out water pumps and batteries but little in diagnostic. Any help is appreciated.
 
Thanks for the help. No I can't check for trouble codes. There is no power to the obmII or to any trouble lights in the instrument cluster. All fuses are good. They were there at first and now they are gone. Im not sure if the two problems are connected or not. I read the article but it pertained to LT type engine using a distributor and ICM. I have an LS engine. No distributor and the ICM is integrated into the PCM (as I understand it). Could a faulty Body Control Module cause the PCM not to fire the coil packs and be the cause of the trouble light problem?
 
you have the shop manual and it doesn't have any wiring diagrams to trace the power to the pcm ?
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Yes I have the shop manuals and yes there is battery power and ignition on power to the PCM as well as all grounds. The PCM is not telling the coil packs to fire for some reason. There is no break in any of the wiring to or from the PCM. My question, other than the crank sensor, which has test ok, what signal or lack there of, does the PCM need that would prevent the PCM from firing the coils?
 
You stated "There is no power to the obmII or to any trouble lights in the instrument cluster.", what do you mean by obmII ?
 
I had I guy ck for trouble code through the OBM data port and he said there was no power to the data port. I need to confirm that but I read that the data port shares power on the same circuit as the cig lighter. That circuit test ok. The trouble lights were off then came on and now are off again. This thing is a electrical nightmare. It cranks , has fuel, injector pulse, 12 voilt power to the coils and to the PCM. All grounds test ok as well as the crank sensor. The PCM is just not firing the coils. We even ordered another PCM flashed to our VIN with no luck. Im not sure the no start and no trouble lights are connected. I'm trying to find someone with the tool to live read the PCM while cranking. Maybe that will shine some light on it. I appreciate the all suggestions. I am stumped.
 
the tool isnt going to help if you have no power at the port. The cigarette lighter fuse does supply power but with the electrical issues you are having I would take a very close look at your engine compartment fuse box. Disconnect the battery and start checking that box by unbolting it and looking at the incoming wire connections.
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