Hey guys i was told my alternator wasnt working on my 99 gt a couple of weeks ago.A friend of mine had a spare 01 gt alternator which he let me burrow till mine shipped got shipped in.The 01 pulley is bigger than the 99 but i put it on since i needed the car.Later that night i had the service engine light go on.the car feels a lil different but it feels like it responds a lil better than before..so i want to know if this 01 alternator is doing any harm to my 99??

 

I'm not 100% on this but putting under drive pulleys to have your pulleys spin faster right? Wouldn't a bigger pulley make it spin slower maybe not charge it all the way?

 

If the pulley was bigger, then you also had to change the belt size, as it wouldn't work... unless it's just a teensy bit bigger. The tensioner for the serpintine would be at it's upper limit of retraction, and working hard to compress the belt. A V belt wouldn't be any issue.

The bigger pulley would make the alternator spin faster, yes, but it wouldn't be a huge issue.

Also, it's not impossible that the wiring isn't right. But I kinda doubt it.

Service engine doesn't mean alternator's causing it. You need to read the codes to get what it wants. It could be incredible timing that your mass air sensor quit on you, for example.

 

Well its not big of a difference but the 01 alternator is a bit bigger may e i can post pics tommorow.I been having the car for a while n i never had the engine light go on until i recently swapt the alternator.how could i read the codes tho?

 

The new

 

The old

 

I bought the new one feom americanmuscle...i still have my check engine light on!!?

 

What code is it?

 

It was a coil # 8 got it fixed