Obscene678

I recently installed some Pacesetter LT headers and CAI on my 2005 GTO. There were some fitment issues, like the steering knuckle rubbing on the header cause the steering to lock up at WOT. After we fixed the steering problem I took the car to Vengeance Racing for a street tune. The car feels faster and I couldn't be happier. However, when I come to a complete stop the idle gets pretty rough, not the shakes the motor normally produces, but kinda like a constant rumble in the car. I have a feeling it could be an exhaust leak. Any ideas of what the problem could be? Thanks for any and all help.

svede1212

iTrader: (3)

That's tough. I'd be curious if you have an intake leak. They are mostly noticeable at very low RPM. It's hard to tell without someone seeing or hearing it tho. LTs add a considerable amount of sound as they are much thinner than the cast iron manifolds. Exhaust leaks would only maybe affect it if it was ahead of the front O2 sensor.

Slickgoat05

strange..i have an 05 with pacesetter LT's and have no "rough" idle...something u need to look into

gto866

headers are usually a win/win mod. you may loose some torque on the 1 7/8 tubes
I did 1 3/4 on my goat to prevent this

TyCZ28

sounds exactly like what my 97 Z28 i had was doing because the headers were touching the k member and floor pan.. check for clearances... the vibration always goes away once you accelerate but at idle it will vibrate everything

redtan

iTrader: (5)

An exhaust leak is not going to cause your car to shake so that's out. Yes you may have exhaust leaks from the shitty pacesetter clamps, but that's not the source of your shaking.

Do you have any codes? I have a feeling this might be electrical related as in you have some rough idle from bad o2 sensors or plugs/wires. Those are common problems given that they are always being touched when doing headers so mistakes can happen.

svede1212

iTrader: (3)

Something I forgot was cracked plugs or wires from the install.

Obscene678

Thanks for the help everyone. Quick update, the problem seems to have fixed itself. I haven't felt the shacking in a few days and when we got it on a lift we didn't see anything touching.

adamc45

i had a slightly rough idle on first start up when i installed my kooks. my tune made it much smoother. what numbers did u put down?

Obscene678

363/354

adamc45

thats awesome. my 04 put down 326/344 with stock air box and my kooks.

Obscene678

Makes sense, there is about a 50 hp difference between 04 and 05.