hi this is my first post. I think i blew my pcm, i wasent paying attention and hooked the battery up wrong. now when i start the car and put it in first gear and drive the gauges go all crazy and the lights to flashing off and on and the ignition is dinging. Is it true that the pcm's from the 97-99 cavalier/sunfires are the same? all you have to do is just reprogram the pcm to your engine and tranny?

Thanks

if ur pcm was gona the car wouldnt start



MY 2003 SUNFIRE 15.63@87.86mph

"A N/A ecotec is not gonna give Honda's and Mitsu's that much of a run for their
money unless their blown or bottle fed.GM is still smokin crack!"
~1QWKZ24
www.streetracing.org, 08/2001

so what could cause that problem? bad alternator? im so lost for ideas

If you connect the alternator up with reversed polarity you have almost certainly blown the diodes in the alternator.

I think all your warning gauges and lights are being caused by low battery voltage.
Remove the the alternator and get it checked out in a shop.

Fully charge the battery with a charger if you can or have that charged at the shop, before you run the engine with the replacement alternator.

You could also fit a serviceable alternator from a junkyard but remember to always disconnect the battery first and connect it up last, making sure the polarity is correct before you do so.


Let us know how you get on

Hope it's not expensive


Alont

ok thanks a lot, i will take the alternator out tomorrow and get it checked and let you know.