01 c5 with .592 or something size cam, afr heads, lingerfelter polished intake, veram intake, cooks headers no cats, b & b tri flow touring exhaust. car idles good if it ever idles down. but idle hangs up when ever you come to a stop, sometimes as long as a redlight. i can drive without giving it gas. idle handup is 2 grand or better. what could be causing this. thanks

 

It could be a few things, id start with getting your car to a professional tuner and have it tweaked with LS1 edit or something.

 

There are 16 different idle strategy adjustement tables located in the C5 Corvette PCM depending on model year and software used. All of them must be adjusted properly in tandem for a successful, stable, non-stalling idle in all ambient conditions and scenarios. Proper VE adjustment also plays a big role in proper engine drivability, especially with long duration camshafts.

 

I have seen people drill a small hole in the TB plate???

 

We've seen that too and that method is just a band-aid fix for those folks/tuners that don't have the kow-how or inclination to spend the time to properly calibrate the idle strategies that some of these engine combinations require. The C5 Corvette stepper-motor actuated throttle blade has a nearly infinite amount of electronic adjustment since there is no separate IAC motor to deal with, so why someone would "punch a hole" in a perfectly good throttle body blade is completely beyond us...

FYI if interested.

 

That is really mandatory after a decent size cam install with other mods. Have those darn cooling fans reset to a lower temp and a new thermostat installed while you are at it.

 

Is your car an auto or 6 speed? You have no Cats, so you better have rear O2s deleted in your PCM. judging by cam lift, I would say you definitely should consider an LS-1 edit. Actually I don't see it as a choice , but a must do.

 

it is a 6 sp, i also noticed that when i was on the hwy, that when i geared down to 5th gear at 65mph, the speed dropped but the idle wanted to stay at 2,000. could it be the throttle body not letting enough air in, it is the ls1 stock throttle body. i've had all the check engine lights tuned off so far, i don't have any others.

 

Your idle would "hang" in the event you drilled a hole too big. So don't think about doingthat. Make sure your intake fits properly and all of your post MAF plumbing is on correctly. Make sure your intake did not get installed on top of anything and make sure that when it was polished the sealing surface remained perfect and the intake itself did not warp.

Also

In my case drilling my t-body was the best thing I ever did to my car to get it to idle. It is a safe/easy fix. It is how it was done prior to LS1 edit. And LS Edit can adjust the throttle blade position but your idle will also be higher as a result so you haveto tune around it. It is just a motor that needs more air. A hole will accomplish that easily and will not set any codes. The F-bodys come stock with a hole.

After my cam my car would often stall out at lights. Two months later after I put the LG's on the car stalling was way worse when coming to a stop. Drilled a hole and it ran perfect. No codes, Idles @ 800 ran great. Put down great numbers and ran 12.70 on street tires. 8 months later I put AFR heads on and an ls6 intake - still ran perfect, no codes idled at 800. No $500 tune required whatsoever. Last month I finally got it tuned and told them not to touch the idle. Tuner said it was spot on anyway.

Anyway plenty of reputable tuners will recommend drilling a hole after installing a cam to get it to idle. Show me an example of one problem associated with it other than drilling too large of a hole and having the idle hang.

 

it idles great when it actually comes down, it just wants to idle high for a long time, and while driving at certain speeds there is no need to press the pedal, would drilling help this as well.