92 Daytona R/T PCM problem

[bananacharger]

Hello all-- I'm wondering if anyone has run into this problem before. I have 2 92 Daytona R/Ts; one was purchased recently for parts to finish my first one. As it turns out, the one I bought last month is not in nearly as bad a shape as expected (the guy I bought it from found it in a wrecking yard about 12 years ago. He realized what it was and bought it complete with the intention of fixing it. He never got around to it and I bought it). It has at least a broken rocker, but once I cleaned out all the pack rat turds and nests, it looks like it would be salvageable. At this point, I'm trying to find out what works and what doesn't. The SBEC was disconnected and opened up, so I cleaned the terminals, put some heat sink compound between the chips and cooling fins, reassembled it and put it my first Daytona, which runs fine. With this controller in it, it will turn over and start great, but it only runs for about 1-2 seconds before it shuts off. It can be restarted any number of times and runs smoothly, but will only run for a second or so before it dies. There are no fault codes (I checked multiple times and only get 12 and 55) and I know it's the controller since my original does work alright. One difference between the two cars is that the new one has the factory anti-theft system while my first doesn't (at least, I think it does; there's a hood switch on the fender in the factory spot). Would the engine cutting off be part of the anti-theft system being triggered? I'd think that would all be in the BCM, but I'm not sure. Your thoughts would be appreciated. Thanks!

[marc]

Is your fuel pressure good?

[bananacharger]

Is your fuel pressure good?

I would think so, since it runs great with the original controller back in. Or do you mean that the PCM may have a fault which causes the fuel pump, relay, ASD, etc. to not be working right?

[marc]

I would think so, since it runs great with the original controller back in. Or do you mean that the PCM may have a fault which causes the fuel pump, relay, ASD, etc. to not be working right?

I missed the part of it runs fine with the 2nd SBEC, sorry.

[Reaper1]

I do believe the factory anti-theft is messing you up. I *think* there's a way to bypass it. I've never dealt with one in person, but I have a couple of friends who have. Maybe Gary Donovan or NAJ could help you (Jackson, too)?

[sdac guy]

I do believe the factory anti-theft is messing you up. I *think* there's a way to bypass it. I've never dealt with one in person, but I have a couple of friends who have. Maybe Gary Donovan or NAJ could help you (Jackson, too)?

I can second this. The problem you are having is the classic symptom of an ECU which came in a car with factory alarm being used in a car without it. It will start, run for a second or two and then die. The factory alarm system (which runs in the BCM) sets an alarm bit in the ECU, and as long as that bit is set, the above symptom will happen.

There was another thread here where this was discussed and I believe Rob (Shelgame) had a way to resolve the issue.


Barry

[bananacharger]

Thanks Reaper1 & SDAC Guy; it seems that the controller from the new to me Daytona with the factory anti-theft is looking for a signal from the body module that everything's OK, but it's not getting it and then cutting off the engine. I'm just trying to see what works in the new one, which doesn't run right now. It looks like the controller will be OK in it if/when I get the car going, but I'll pull the engine and going through it and all the other systems first. For a car that's sat outside in a field for 13 years, this Daytona is amazingly rust-free. I bought it just for the ground effects and a few other pieces with the thought that I'd sell off the rest, but it looks worth saving.

[ShelGame]

I can second this. The problem you are having is the classic symptom of an ECU which came in a car with factory alarm being used in a car without it. It will start, run for a second or two and then die. The factory alarm system (which runs in the BCM) sets an alarm bit in the ECU, and as long as that bit is set, the above symptom will happen.

There was another thread here where this was discussed and I believe Rob (Shelgame) had a way to resolve the issue.


Barry

Yes, I do. And it is most certainly the anti-theft software doing it's thing.

Actually, if you have one of my SCI cables and MP Tune, you can fix it yourself. There's an option in MP Tune to 'erase the EEPROM'. This is all that is needed. The anti-theft bits are stored in the processors EEPROM. If you erase the EEPROM, then the anti-theft bit gets reset.

Or, you can send it to me and I'll re-set it for you. You just pay for shipping it both ways...