Whats wrong with my idle? Sputtering bad like i have cams almost??

[FastGS-T]

Alright, put on a Cometic head gasket, and arp head studs. First time ever tearing into a motor, but i got it to run fine with no leaks... But now my car idles crazy (put put put) and i got the idle to stay around 850-900 but still it will lobe alot and go down to like 600rpms and try to die.. But its "put put putting" really bad like a rhythm almost

plus my stft and ltft are 5% and 11% and they will not change.. but as far as driveability the car is driving good. But after letting off the gas sometimes the afc is reading 1-3% throttle and I gotta tap the gas to get it to go back to 0%

 

[1991GSXAWD]

most common thing overlooked is the exhaust cam being 1 tooth off when reinstalling the timing belt, check again to be sure that both cams line up at their marks, vaccum leaks will make it idle poorly too.

 

[andymoraitis]

Well said. I've had this happen before and it created the same symptoms. Re-check the cam timing marks and let us know what you find.

Andy

 

[Stapl3]

Are you letting the car idle for ~5 minutes before checking the ltft and stft?

What thickness is the HG?

Has your head or block been decked?

 

[FastGS-T]

it is a cometic head gasket... i took the head to a machinist and he checked it out as fine. And he said it had been shaved before because the valves were already sitting down past the head surface, and he cleaned off the head surface for me...

i cleaned the block surface as best i could and stuck the head on.

all information was after letting the car idle about 10 minutes.. and some driving and then more idling

 

[Stapl3]

Bingo. Decked blocks or heads mess with timing. If you deck your head or block, you MUST get adjustable cam gears.

Your timing is messed up.