We've put just a little over 100 miles on our new CTS and I was wondering about something. We have the base 263 HP engine. What does everyone seem to have for an idle speed once fully warmed up? Our seems to be around 750, which seems a little high to me. I was expecting it to be around 500 RPM.

Also, when at a light the other day, I felt a slight lurch from the transmission while my foot was on the brake at a light. It sort of startled me and I checked the rear view mirror to make certain I hadn't been bumped by the car behind me. Anyone else experience something like this?

I have the DI and my idle is probably 600-700 rpm

I have the base 263-hp motor, manual trans, and my idle speed sits around 5-600 rpm. When I first start the car, I believe it sits around 1500 rpm for approx. 15 seconds, then down to 1000 rpm for another 15 seconds. After that, it is 5-600 rpm. This is normal as far as I am concerned. 750 rpm doesn't seem too far off. To be safe, I would bring it to the dealer though. Should be a very simple fix.

My wife has a 2008 Awd regulaur 3.6l with about 350 miles on it. She is feeling the same "Lurch" that Crackerzot described in the original post. Has anybody else felt this?....and her idle seems to fluctuate at a stop in gear also. Any help or input would be appreciated.

I wouldn't spend too much time worrying about it for a few hundred miles. When my car was new it would idle high, around 900 rpm. After about 400 miles it started to drop down to about 600 but would still go up every now and then. By about 800 miles it never went back up over 600 except when cold. Clearly something in the new car is causing it but I don't know what. Just give it some time.

I wouldn't spend too much time worrying about it for a few hundred miles. When my car was new it would idle high, around 900 rpm. After about 400 miles it started to drop down to about 600 but would still go up every now and then. By about 800 miles it never went back up over 600 except when cold. Clearly something in the new car is causing it but I don't know what. Just give it some time.

That is my intention at this time...I figure either the car will get used to my wife or my wife will get used to the car..lol Thanks for your response...I am still a little concerned with the "Lurch" feeling....she described it exactly like she felt like she got bumped and looked in the rear view. Time will tell.

I have the 3.6 in an STS and the specifications call for 600 rpms (A/C compressor off), 750 rpms (A/C compressor on). Of course, at startup, you are going to see approximately 11-12 hundred, then after warmup, coming down to specs.

For what it's worth I also felt the "lurch" a few tmes while stopped at a light. Like the above posts, it felt like the car got tapped from behind. The car has about 800 miles. I have the 263 HP w/AWD.

For what it's worth I also felt the "lurch" a few tmes while stopped at a light. Like the above posts, it felt like the car got tapped from behind. The car has about 800 miles. I have the 263 HP w/AWD.

Hmm...My Wifes car is a 263 HP w/AWD also. Anyone else? Any Ideas? Service Bulletin maybe?:confused:

Mine is a standard with 263 and RWD. I do notice that it always idles faster when I first start it up, even though it's still summer. I always feel like a crappy shifter trying to manage the higher rpm for the first few minutes before the idle drops down to normal. It freaked me out at first, but now I've just come to accept that it will always idle faster for a few minutes.