OK so heres the problem, when i turn my car on and the air conditioning is off the engine runs fine, but then when i turn the ac on my rpms go from 900 to 500 to 1000 and it just keeps jumping up and down. and also there is a check engine light that is on now and its P0315 which has to do with the crankshaft sensor. i dont know what to do..... please help!

 

anyone? 22 views and no help

 

It is a timing issue (tune). mine does it to

 

(1) How many miles on your car?
(2) Any maintenance performed recently?
(3) Mods?


need a little more detail than what you provided. BTW, what engine do you have?

 

69000 miles on it, and i did just put a stage 2 kit in which includes injectors, spark plugs, pulley and new pcm all by zzp.

 

what size injectors and pulley? Did you go with the oversized tensioner, or gm stage II belt? Did you get a canned tune from them? Did you verify the spark plugs were properly gapped at .035? Also, do you hear any funny noises while it's idling or driving as well?

 

#50 injectors and a 3.1 pulley, i went with the oversized tensioner but the bearing was messed up so i sent that one back to zzp and put the stock tensioner back on.. waiting for the new tensioner. i did get the tune from them. and i also did check to make sure that the spark plugs were gapped at .035. and no, there are no funny noises, except when im idling and the ac is on the rpms go crazy.

 

so you have the stock belt and the stock tensioner on there currently?

 

yes the stock belt and stock tensioner. and the belt is pretty tight on there.

 

that's most likely your issue. That belt is pretty long no matter how tight you get it on there. Even a little slack is gonna throw the timing off. If I were you, I would ditch the over sized tensioner and just get the gm stage ii belt. It's like 40 bucks and you can use it with any pulley available for the m62. I believe at some point, you'll have to end up ditching the over sized tensioner for a certain sized pulley.

 

so your saying just go buy the new belt and keep the stock tensioner on ther, and not put the oversized tensioner on?

 

Yeah, make sure its the Stage II belt. and keep the stock tensioner.

Btw, where are you located in MI?

 

buy the shorter belt that GM puts in their Stage 2 kit. Don't just get another OEM belt because that won't fix a thing. And yes....ditch the over sized tensioner.

 

i live in bloomfield hills michigan, and ok i will try that tmrw. how hard will it be to just put the belt on?

 

uh, been a while since I've messed with s/c's. But it's not that hard, provided you don't strip your tensioner.