dereklburt

iTrader: (3)

I just installed some CNC LS6 heads, fast intake, and a 90mm throttle body on my LS6. I had it tuned but the car's idle is hanging when I decelerate and then it will eventually drop down to idle. There are times when I stop quickly that the idle will drop way down and the other day it almost stalled. I checked everywhere for vacuum leaks and did not find any. Thoughts??

I did not put sealant on the rocker arm bolts and someone mentioned that they can sometimes pull vacuum. I still have to install my hardened push rods, so I will try that tonight but I am stumped and it is very annoying. I also want to figure this out as at $400 a tune, I can't just keep running it back.
Thanks for any help/input

dereklburt

iTrader: (3)

I forgot to mention. My check engine light is also on. Today the idle dropped so much that it died on me. I am going to pull everything apart. I am wondering if it could be the O2 sensor or something? Is there a easy way to diagnose? I am going to replace my header gaskets as well as I think I might have a small exhaust leak.

Anyone??? It seems to run fine when accellerating once the revs are up a little. Seemed to hesitate a minute when the revs are low. I was also told by my tuner that he was not able to get a lot of timing out of it. At the time, he thought it might have been the gas and recommended using Shell.

smokeshow

iTrader: (17)

Tune needs more work. Is it drive by wire or cable?

Jasons50

iTrader: (1)

I would get your cars computer scanned to see why C.E.L. is on. Did the car do this right after tuning? If so I believe I would make him fix it, or get a refund to find another tuner. Does the car smell like it's running rich, making more heat than usual? I would get this resolved promptly, if to lean/rich could be hard on engine. Goodluck

edcmat-l1

iTrader: (10)

Yep. It's got some tune issues.

dereklburt

iTrader: (3)

I didn't really notice it right away but then again, I did not get a lot drive time as I picked it up and drove it home and then took it to an event the next day. The car drives fine except on idle. The engine light didn't come on until the following day after taking it to an autocross event. It does seem like it is running rich. The only thing I did after the tune was try to tighten my exhaust a little. I know that the rear O2 sensor was close to the bolt and my rachet was stuck for a second and I had to jiggle it to get it out. It was pressed against the one O2 sensor but that is the only possible thing I can think of.

My Fast manifold also was ported and at one time was repaired prior to me buying it but the repair looked good. I sprayed carb cleaner EVERYWHERE and even under the manifold but it did not change the idle at all. I am taking it back in the morning, so hopefully it can be figured out. I really don't want to pay another few hundred for a tune/repair if the tune is the issue. It was taken to a very reputable shop that is well known. Hopefully they will admit it if it was the tune.