Start an die conditon
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Start an die conditon Have a 98 firebird with 3.8L That i just rebuilt the engine completly when i put the motor back in the secerty light stays on solid and it starts and revs high for about 3sec and then dies. if i play with the gas i can keep it running at high rpm but as soon as i let off dies instantly. I have scanned for codes but only codes i get is an emission code.
Joined: Nov 2003
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From: Jacksonville, FL (originally from Toronto Canada)
The SECURITY light in the instrument cluster indicates a problem with VATS. It doesn't recognize the resistor pellet in the ignition key. That triggers two actions... it disables the ground to the starter relay and it won't send a fuel enable signal to the PCM. If the key problem happened while the car was already running then the system will assume it is a fault and still allow the car to start. But if it happens when you're first trying to start the car then it won't allow the car to start.
Did you do anything with the PCM when you reinstalled the engine? It's possible that it isn't getting that fuel enable signal although one would think it wouldn't run at all in that case. It could be that the SECURITY light is just a coincidence and you just have a run-of-the-mill engine problem such as fuel starvation, bad spark, timing, etc.
Did you do anything with the PCM when you reinstalled the engine? It's possible that it isn't getting that fuel enable signal although one would think it wouldn't run at all in that case. It could be that the SECURITY light is just a coincidence and you just have a run-of-the-mill engine problem such as fuel starvation, bad spark, timing, etc.
Launching!
Joined: Jun 2012
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Have a 98 firebird with 3.8L That i just rebuilt the engine completly when i put the motor back in the secerty light stays on solid and it starts and revs high for about 3sec and then dies. if i play with the gas i can keep it running at high rpm but as soon as i let off dies instantly. I have scanned for codes but only codes i get is an emission code.
Joined: Nov 2003
Posts: 6,216
Likes: 236
From: Wichita KS / Rancho San Diego
Since your security light is on, that system is definitely involved. We had a similar problem with our Montana van and security system reset solved it. You should be able to do that with a good scan tool.
Joined: Nov 2003
Posts: 11,328
Likes: 346
From: Jacksonville, FL (originally from Toronto Canada)
Unfortunately, VATS in an f-body can't be reset or programmed out. It can be bypassed (using resistors to simulate the correct key) but the BCM is not programmable so a scan tool won't help.
I suggested that the SECURITY light may be a coincidence because the car will start and run (although not well) which would indicate that the light is on due to a VATS fault which was detected while the car was running. When that happens, VATS will allow starting on the assumption that it's a fault rather than a theft attempt. If it was VATS causing the problem then the starter would not turn at all and the fuel would be completely cut off so no amount of jockeying the pedal would keep it running. Add that to the fact that it's a new/rebuilt engine installation and I would guess that it's something unrelated to the security system.
I suggested that the SECURITY light may be a coincidence because the car will start and run (although not well) which would indicate that the light is on due to a VATS fault which was detected while the car was running. When that happens, VATS will allow starting on the assumption that it's a fault rather than a theft attempt. If it was VATS causing the problem then the starter would not turn at all and the fuel would be completely cut off so no amount of jockeying the pedal would keep it running. Add that to the fact that it's a new/rebuilt engine installation and I would guess that it's something unrelated to the security system.
Joined: Nov 2003
Posts: 6,216
Likes: 236
From: Wichita KS / Rancho San Diego
Yes - I was confusing experiences with VATS with Passkey III. It's odd that the symptoms were almost identical to what he's experiencing.
Both my son's Firebirds had to have the VATS bypass. On mine, the security light came on one day as I was driving. It's been that way for about 10 years with no other issues.
Both my son's Firebirds had to have the VATS bypass. On mine, the security light came on one day as I was driving. It's been that way for about 10 years with no other issues.
