[Danno]

Recently bought a '92 Hatch with a 347 stroker in it. It didn't run real well, but I knew all it needed was a tune. Took it to the speed shop. They tuned it, and it ran like a breeze. I was very, very pleased with it. Alternator went out that night on the way home from the speed shop. Ordered a new alternator and installed it last night. No issues with the install - everything went exactly as planned. I fire up the car and it runs for a second and stalls. Fire it up again and it does the same. I'm in VA and it's about 30 degrees outside. If I goose the gas, it'll keep running, but the gas pedal is VERY unresponsive (if I lightly tap or stomp on it, it thinks about it, then tries to rev, then wants to stall again). I call the speed shop and say WTF, it ran beautifully and now i can't even keep it running without goosing the gas. Speed shop says the computer "learns" some of its tuning and stores that in some kind of hybrid of CMOS/RAM (For you non-IT people, CMOS is what keeps time on your computer - it's powered by a battery and doesn't lose memory when you turn off your computer, whereas RAM only remembers things as long as the machine is powered on; as soon as it shuts down everything in RAM is gone). So apparently the computer can hold this knowledge for a little while if the battery is unplugged, but after 20 minutes or so, it dumps it and has to start from scratch????

My questions are:

1) Is this legit, or did the shop do something funny with the computer that now backfired when I unplugged the battery for 30 minutes?
2) At this point I can't get the car to run long enough to get anything out of it, so I'll be using one of my free tows with AAA to get it back to the shop (something I like to reserve for true emergencies) - is there anything I can do to "jump start" the learning curve of the computer?
3) My air/fuel gauge is showing very, very lean (almost not registering on the gauge). That said, am I at risk of hurting the motor just to get the computer to "learn" the tune again?
4) What else don't I know? (probably a lot).

Any insight you could provide I'd be grateful for. Thanks in advance.

Danno

[flattusmaximus78]

Your tune has nothing to do with a a learning process. It's a chip. Your getting bs'ed.

[Danno]

OK, so did the chip get damaged (erased) or something when I unplugged the battery? If so, is there a way to fix it?

[VM0824]

chips generally also have this type of memory, but they also have backup battery similar to a desktop to keep the memory alive. i think the one on my chip lasts something like 10 years. so that shouldnt be the problem. to me it sounds like your in maf limp mode, check connections maybe you accidentally bumped something loose while changing the alternator.

[1LOUDGT]

I would take the alternator and your battery back to the parts store and get them checked first. What alternator did you purchase? If they check out ok then I would re install and start checking all your connections. Check MAF, TPS, Starter, Solenoid, etc. Also might want to make sure your chip isn’t making contact with the computer box.

[TinyWeyant]

No idea whats really wrong with it but man I hope you figure it out... Keep us posted

[1LOUDGT]

Pretty sure there is no limp mode in a fox body.

[VM0824]

i believe there is. unplug your maf sensor. it'll throw a cel and go into limp mode. essentially it'll switch from mass air to alpha n strategy. basing its calculations solely on throttle position and rpm.