NEW PCM, car won't start
Thread Starter
Melting Slicks
Joined: Jun 1999
Posts: 2,949
Likes: 23
From: Bowling Green KY
NEW PCM, car won't start
OK so I've ripped all the factory crap out of my car - I'm putting a Painless Performance LT1 fuel injection harness on and also one of their chassis harnesses. As recommended by Painless, I'm using a brand new (well, remanufactured) 94/95 Fbody PCM straight from my GM dealer. Just to make sure, I talked to Brian at PCMforless and you absolutely do NOT have to have the dealer do any flashing, you should be able to take this thing home, flash it, and take off.
Car is turning over so no problem there. Fuel pump is energizing. When I turn the key the check engine light comes on, which as the Painless manual says is good, that tells me the connection is there to the PCM. Also I can connect fine through Datamaster and Tunercat, Datamaster is registering no codes whatsoever.
But I'm getting zero spark - coil does have power but if I crank the car none of the terminals on the Opti connector are getting power, so in other words the PCM is not sending a spark signal, don't know why?
I have loaded a .bin file through Tunercat that should absolutely work, same one I had in the car previously w/ a 95 Vette PCM and same one that was in the car when it originally had a 95 Fbody PCM, so I know my .bin is good and I have tried some other .bin's as well that I know are good.
I have turned off VATS and also the Painless kit has a VATS-bypass module, though I'm still not so sure that VATS couldn't be in play here somehow. . . . does VATS shut off spark or fuel???????????? If just fuel then it ain't VATS, unless VATS just shuts off injectors.
Also, the fuel injection harness is grounded by a bolt being screwed into the back of the head, should I ground it to the engine block instead? (though the head should be grounded through the head bolts)
Any ideas? Any help appreciated.
Car is turning over so no problem there. Fuel pump is energizing. When I turn the key the check engine light comes on, which as the Painless manual says is good, that tells me the connection is there to the PCM. Also I can connect fine through Datamaster and Tunercat, Datamaster is registering no codes whatsoever.
But I'm getting zero spark - coil does have power but if I crank the car none of the terminals on the Opti connector are getting power, so in other words the PCM is not sending a spark signal, don't know why?
I have loaded a .bin file through Tunercat that should absolutely work, same one I had in the car previously w/ a 95 Vette PCM and same one that was in the car when it originally had a 95 Fbody PCM, so I know my .bin is good and I have tried some other .bin's as well that I know are good.
I have turned off VATS and also the Painless kit has a VATS-bypass module, though I'm still not so sure that VATS couldn't be in play here somehow. . . . does VATS shut off spark or fuel???????????? If just fuel then it ain't VATS, unless VATS just shuts off injectors.
Also, the fuel injection harness is grounded by a bolt being screwed into the back of the head, should I ground it to the engine block instead? (though the head should be grounded through the head bolts)
Any ideas? Any help appreciated.
Last edited by DVNCI; Mar 17, 2009 at 11:54 AM.
Thread Starter
Melting Slicks
Joined: Jun 1999
Posts: 2,949
Likes: 23
From: Bowling Green KY
