Caniac

Picked-up my new 09 Tahoe LT Z71 last week from the dealership. The vehicle I wanted was in a neighboring state so I had to wait while they sent a driver. They gave me a new Tahoe off the lot to drive for 4 days while I waited. The loaner was brand new and had 8 miles on it. I drove about 180 miles on the loaner and it had a smooth idle. I noticed because I drove a duramax diesel 2500HD for 7 yrs prior.

I picked up my vehicle and it now had about 240 miles on it with a lot of interstate to deliver to my location. My truck has a somewhat rough idle. It's not major but enough to shake the truck a little. The RPM gauge bounces a litle as well. Its not noticable from the outside our by sound. If you hae your foot on the pedals and hands on the wheel, you feel the shake. The truck also seems a little sluggish on the starts, like its stumbling. Not sure if I'm just being over sensitive. Also not sure if the sluggish/stumbling starts is due to the 6spd tranney.

Do any of you 2009 owners notice a slight rough idle? I don't want to waste a day at the dealership if its "normal". I'm guessing they will say that anyways. Hopefully, the trnasit driver didn't abuse the truck during the "break-in" period on the drive into town.

Any help is greatly appreciated!

SabrToothSqrl

I've had dozens of problems w/my 09 LTZ, but no rough idle.

I'd take it in ASAP and get that tahoe loaner back.

Jumper

Thanks for the reply on my post about the shudder. My Z71 idles right at about 500rpm and it is smooth as silk. The O4 LT we had before you could feel the engine rumble a bit but not on the new one. We really like everything about it, but this surge or shudder problem in very annoying. Seems worse when its hot too. I would take it in about the rough idle. I'll bet they can fix that really easy. It should be smooth.

Caniac

Going into the shop on Tuesday. I'll post the results...

Caniac

Well, as expected, the Dealership wasn't able to find anything and dismissed it by saying "Its normal they all do that!". There weren't any codes stored and everything looked okay. I'm going back tomorrow to meet with the Service Manager and check some of the others on the lot.

Has anyone else noticed a rough idle? My truck shakes when idling. You can feel it in the seat. The Manager claimed that the motors are programmed to lean out when idling to conserve fuel. Sometimes if its too lean it'll develop a "wobble" as he put it. Anyone know if this is true or BS.

I traded in my 2500HD truck with 140,000 miles and it had a nice idle and was much stronger than this engine. Wished I kept it now.......
Thanks!

Jumper

My wife claims she practically has to floor our new Z71 to get it to move. It's much slower than the 04 LT we had. I think the shift points on the new 6 speed are worse than the old 5 speed so you have to give it a lot of throttle to get it to downshift and accelerate.

KMeloney

No rough idle here -- just the annoying surge when nearing a stop from slow speeds. Really, really annoying.

in2pro

Every engine is going to have its own characteristic, you could try running a bottle of fuel treatment through and also try a full tank of gas from a different gas station and perhaps using mid grade.
As for acceleration, the GMT900 is throttle by wire and no longer controlled by a cable this could account for the sluggishness in acceleration in addition to the 6speed tranny, try enabling the "tow haul" mode and see if that produces a better response....

73shark

Thought the 04s had a 4 spd. Also the NBS has something called torque management which makes the truck feel like it's dragging an anchor when you take off from a stop.