slight engine vibration at low RPMs

[KeithNorris]

I bought a used 2005 CTS with 35k miles about 3 mos ago. Have recently noticed a slight vibration coming from the engine at low RPMs while cruising or at idle. Mechanic did some sort of emissions test on the carbon build up?? That didn't seem to help anything.

Any thoughts or experience with this issue??
Thanks

[Cadillacfilter1]

I would clean the throttle body..change the fuel filter and see how that works.

[Rolex]

Originally Posted by Cadillacfilter1

I would clean the throttle body..change the fuel filter and see how that works.

I don't imagine it's the fuel filter but I agree with cleaning the throttle body 100%.

Here's a post from the other day on this very thing:

http://www.cadillacforums.com/forums...68-post11.html

[KeithNorris]

thanks for the advice. I bought some Lucas Oil fuel injector cleaner that I will try per some other's suggestions, can't hurt I guess. Is cleaning the throttle body easily done by a dealer? I have no idea how to do that myself.

[Rolex]

The best injector cleaner on the market IMO is SeaFoam.

Dirty throttle bodies and rough idling is starting to become one of the more common issues in this forum. Learn to do this yourself and save some $$$. One user here just said a dealer offered to so it for $400. There's nothing easier to do:

Originally Posted by Rolex

Throttle body cleaning instructions:
1. Buy throttle body cleaner (NOT carb cleaner)
2. Disconnect the air intake tube from TB and set it aside
3. Have a friend stand on the gas pedal (with the car turned off) to open the valves on the TB
4. Stuff a clean rag down the TB to stop trash from going into the engine
5. Spray the heck out of the TB, valves, and TB opening with the TB cleaner. Use a soft tooth brush to clean the valves and the area around the Tb opening where the valves make a seal.
6. Remove the rag and reinstall the air intake.

Pocket the $393 you saved.

[KeithNorris]

thank you for the advice and instruction. I traded in a 2005 Toyota Tacoma that I bought new for this 05 CTS. I wanted to get back into a domestic sedan and figured this was the best. I hope I'm right!

[f5world]

Any update?