I have an 07 G5 GT with these performance mods: Injen CAI, OBX race header and catless dp, Tsudo N1 catback. When i start up my car she likes to idle really high until i put her into gear and drive for a little bit. Then sometimes when stoped at a light or idling in general the idle goes up then drops to normal. I understand that some of the times it the fan kicking on to cool the car down but my question is if i get a tune will the idle issue go away?

 

Clean your throttle body to stop the erratic idle. As for the high idle at start up, it's normal until the engine gets to normal operating temp.

 

As long as "really high" isn't 2k or something, yes, that is normal. It should idle about 1100 on a cold start and should drop down within a minute or 2.

The idle speed going up is another issue that several of us have noted (there was a thread going on here in the 2.4 section a little while back). Coming up to a light, just about stopped, clutch in - 1500 on the tach, drops to 800 when I stop completely. Not all the time either, certainly not when the dealer has driven it

Cleaning the tb MAY clear it up for you (helps for some), didn't help in my case

Not sure if a tune will help at all but one of the guys who was having this issue got tuned and his seems to be "fixed"

 

At the start up it does rev to about 1500. The car eventually settles down to about 900-1000 rpm. I hope to get a tune soon. but going to school often puts a halt to spending cash. Thanks for your help guys. By the way cleaned the tp and still high idle at start. I think it has to do with the no Catless dp because it never did it until i installed the dp.