Jupoca

Hi,
I got a new Corvette C6 Z51 coupe 2 weks ago.
The engine speed at idle is 500 RPM.
There is a vibrating annoying noise when sitting in the car, that comes in my opinion from too low idle RPM.
I took the car to Vette dealer and asked to increase RPM at but was told that this was factory setting and they cannot modify it.

Hope someone can tell me if this is true, otherwise how to raise the PMM to 600 or 650?

Thanks,

Jupoca

HawaiiC6

You have a new car and the dealership refused to take care of the problem??? Go to another dealership. Your complaint should not be on the idle but the vibrating noise at idle.

The idle speed is controlled by the computer therefore a tuner will be able to raise your idle. If you have an 08 I am not sure if Diablo Predator is out for the LS3, for the 06-07 the Predator can adjust idle +400/-400 rpms.

But this is the last resort as your new car warranty MUST take care of the problem. You may have a faulty computer.

02-z28

i'm curious, why do you want to raise the idle RPM...?

HawaiiC6

His post states that he is getting a vibrating noise at idle which he feels is being caused by a low idle speed.

The problem is that he went to the dealer and told them to raise his idle which they will not do. What he should have done is tell them of the real problem which is the annoying vibrating noise which occurs at idle speed.

mpuzach

Are you sure that what you're experiencing is abnormal? These engines do exhibit a noticeable amount of "cam lope", felt as a slight vibration or shake at idle. The phenomenon I'm describing is normal so if it's the same thing you're getting my advice is to leave it alone.

User 020720

If it's cam lope that's normal especially on a new car. With my LS2 it was definitely noticeable until my mileage reached somewhere between 5k-10k and now I hardly notice it.

The idle seems a little low to me. My 07 idles around 600 give or take. I'm not sure what the LS3 is supposed to be though. Far as the Predator is concerned I think they're not supporting the 08 C6 just yet.

shopdog

500 RPM is too low an idle speed. It is speced at 600 RPM, and your dealer is required to correct this problem under the federal emissions warranty.

Jupoca

I told them about the vibration noise was the reason I wanted the RPM at idle to be increased. I don't know what cam lope is, but the noise at idle just produces a very annoying feeling in the ears, like if there is resonance in my head, like in a sound box. This vanishes when I push the speedup pedal (increase RPM).
Sabooher, unlike your case I did not notice this problem at the beginning.

C6~Missle

The ECM controls the idle speed.. How many miles on your car... My 08 ran a bit rough when I first got it.. but soon smoothed out with some miles..

FortMorganAl

A rough idle is not right. Usually caused by using cheap gas. My 07 is smooth as glass. One of the smoothest cars I've ever owned.

But you aren't complaining about a vibration as much as a resonance or rumble. That makes me suspecious of the exhaust system. Maybe a loose hanger.

You tried to tell the dealer how to solve the problem not knowing he couldn't do what you wanted. Just tell them you want the resopnance fixed and let them fix it.

Dale Wajbel

I'm having the same problem on my 2010 the idle is 500 i always have my other cars at 600 idle. I just sold a 2006 and the idle on it was 600

rbwinston

Too much info missing here: what year is the car? how many miles are on it? what mods have been done? has there been a tune done on it? he doesn't state that he bought it from a dealer, just that he took it to a "Corvette dealer" which I'm guessing is a Vette repair garage, not a Chevrolet Dealer. 500 RPM is too low and he needs to find someone who has a Tech 2 or similar to get into the computer and adjust it to 600, then see what becomes of the vibration. A Chevrolet dealer that does a significant amount of Vette work should be able to help him or even a private garage that does Vette work.

Turbo6TA

About the only way your going to increase the idle to whatever you want is with something like HP Tuners

2008 Corvette

May be fixed by now. 14 year old thread.