A guy I work with recently bought an 89 firebird, 350, some mild bolt ons were on the car when he bought it, like airfoil and headers and some other crap. Anyway, he has had a hard time starting his car. I noticed he has a hypertech chip in the computer and I took it out and swapped it with a bone stock chip that I had from my 89 formy 350. His car started right up! It idled nicely and drove smooth. When we put his chip back in, same friggin problems, doesn't want to idle, runs junky, and isn't smooth.
On my stock chip, timing is at 6 degrees BTDC, on his chip, it retards itself off the damn timing marks! I can't even guess where he's at when his chip is in! I thought the hyperjunk was going to advance timing, not retard timing, what could be the problem or problems that he is having. He wants to keep his chip and I kinda want to keep my chip also. Please help!
CHIP RELATED INFO
http://www.thunderracing.com/shop-by/ca ... ps_87.html
http://www.motorvation.tv/chips_gm_cars.htm
http://www.tpiparts.net/inc/sdetail/14394
http://www.thirdgen.org/chips-superstock-june1991
http://www.tbichips.com/instructions.htm
ID suggest he buy a stock chip , or get one from a salvage yard as a back-up plan, its obvious that he needs a way to test, so he has the option of using it to test with so the car runs decent, those aftermarket chips are well know for failing occasionally, while they may work and help produce better power you always need a way to test,you can,t make logical choices without knowing exactly what your dealing with you might need to set the ignition timing differently if you change CPU chips, so the first step is verifying what your dealing with and true TDC and what your current advance curve IS.
for those that don,t know on most TPI corvettes the CPU is located up under the dash in the pass foot well, but check your SHOP MANUAL for YOUR car for VALID info and instructions, most chips come with valid instructions
Camaros and Firebirds are located in the bottom of the passenger side dash. Corvettes are located either in the passenger side dash or under the hood by the firewall on the passenger side depending on the year.
Chip installation instructions
Installation is easy.
1. disconnect the battery before playing with the computer.
2. Computer is located in various places depending on vehicle.
Trucks are located behind the glove box liner. Camaros and Firebirds are located in the bottom of the passenger side dash. Corvettes are located either in the passenger side dash or under the hood by the firewall on the passenger side depending on the year. Caprices are located in the kick panel under the passenger side dash. Vans are located under the drivers seat or in passenger kick panel.
3. open the access cover on computer and simply pull the old chip out and put the new chip in. Chip will only go in one way.
4. put everything back together and reconnect the battery.
but Id also suggest taking the time to verify you have the correct ignition timing and advance curve and the correct ignition advance, is functional, that starts with a timing light, verifying TDC (TOP DEAD CENTER) and getting a timing tape installed on your damper and a dent index able timing tab
http://rowand.net/Shop/Tech/GMTPISwap.htm
READ THRU THESE LINKS IT SHOULD HELP YOU GET A BETTER GRASP ON THE PROCESS
the original chip,transmitted at only 160 BAUD,
http://www.eecis.udel.edu/~davis/z28/ecm_swap/870chart.pdf
http://www.eecis.udel.edu/~davis/z28/ecm_swap/
http://forum.grumpysperformance.com/viewtopic.php?f=70&t=1015
http://forum.grumpysperformance.com/viewtopic.php?f=70&t=4683
http://forum.grumpysperformance.com...pic.php?f=70&t=2798]viewtopic.php?f=70&t=2798
viewtopic.php?f=70&t=5372
viewtopic.php?f=70&t=1809
viewtopic.php?f=70&t=232
viewtopic.php?f=32&t=168
viewtopic.php?f=32&t=1401
[/url]
On my stock chip, timing is at 6 degrees BTDC, on his chip, it retards itself off the damn timing marks! I can't even guess where he's at when his chip is in! I thought the hyperjunk was going to advance timing, not retard timing, what could be the problem or problems that he is having. He wants to keep his chip and I kinda want to keep my chip also. Please help!
CHIP RELATED INFO
http://www.thunderracing.com/shop-by/ca ... ps_87.html
http://www.motorvation.tv/chips_gm_cars.htm
http://www.tpiparts.net/inc/sdetail/14394
http://www.thirdgen.org/chips-superstock-june1991
http://www.tbichips.com/instructions.htm
ID suggest he buy a stock chip , or get one from a salvage yard as a back-up plan, its obvious that he needs a way to test, so he has the option of using it to test with so the car runs decent, those aftermarket chips are well know for failing occasionally, while they may work and help produce better power you always need a way to test,you can,t make logical choices without knowing exactly what your dealing with you might need to set the ignition timing differently if you change CPU chips, so the first step is verifying what your dealing with and true TDC and what your current advance curve IS.
for those that don,t know on most TPI corvettes the CPU is located up under the dash in the pass foot well, but check your SHOP MANUAL for YOUR car for VALID info and instructions, most chips come with valid instructions
Camaros and Firebirds are located in the bottom of the passenger side dash. Corvettes are located either in the passenger side dash or under the hood by the firewall on the passenger side depending on the year.
Chip installation instructions
Installation is easy.
1. disconnect the battery before playing with the computer.
2. Computer is located in various places depending on vehicle.
Trucks are located behind the glove box liner. Camaros and Firebirds are located in the bottom of the passenger side dash. Corvettes are located either in the passenger side dash or under the hood by the firewall on the passenger side depending on the year. Caprices are located in the kick panel under the passenger side dash. Vans are located under the drivers seat or in passenger kick panel.
3. open the access cover on computer and simply pull the old chip out and put the new chip in. Chip will only go in one way.
4. put everything back together and reconnect the battery.
but Id also suggest taking the time to verify you have the correct ignition timing and advance curve and the correct ignition advance, is functional, that starts with a timing light, verifying TDC (TOP DEAD CENTER) and getting a timing tape installed on your damper and a dent index able timing tab
http://rowand.net/Shop/Tech/GMTPISwap.htm
READ THRU THESE LINKS IT SHOULD HELP YOU GET A BETTER GRASP ON THE PROCESS
the original chip,transmitted at only 160 BAUD,
http://www.eecis.udel.edu/~davis/z28/ecm_swap/870chart.pdf
http://www.eecis.udel.edu/~davis/z28/ecm_swap/
http://forum.grumpysperformance.com/viewtopic.php?f=70&t=1015
http://forum.grumpysperformance.com/viewtopic.php?f=70&t=4683
http://forum.grumpysperformance.com...pic.php?f=70&t=2798]viewtopic.php?f=70&t=2798
viewtopic.php?f=70&t=5372
viewtopic.php?f=70&t=1809
viewtopic.php?f=70&t=232
viewtopic.php?f=32&t=168
viewtopic.php?f=32&t=1401
[/url]