My '02 S60 (non-turbo) has 83K miles. When in park it has anidle surge. No big deal, just annoying. I have been using "Lucas Upper Cylinder Lubricant" in my gas for the past two fill ups. I thought the surge may be due to dirty injectors. It has not gotten better. Any suggestions????

 

Has your car had the latest Throttle body software upgrade done yet?
If not clean the throttle body and have the Dealer do the recall software.(ETM software)

 

Yes, the car has had the latest software upgrade.

 

Then try cleaning the throttle body.
A dirty throttle body will make the idle surge.

 

What is the best way to get this done? Should I take this to my trusted mechanic or are we talking about a fuel additive?

 

Take it to your mechanic.
Unless you are up to the task yourself.
It is pretty easy to do. Remove the hose from the air box to the throttle body and clean the throttle body with a rag and some brake cleaner.

 

Brake cleaner may be too agressive. It's the IAC I worry about. Unless the butterfly is binding due to crud around the circumference where the valve closes, then it may be a dirty IAC. Don't know if Volvo calls it that however. It should be attached to the TB.

I would suggest getting Throttle body cleaner in an aerosol can that is safe for most applications.

 

The cars with the electronic throttle body doesn't have a IAC motor.
The throttle body adjusts the butterfly to make the car idle.

Brake clean will work fine. Even the dealers use it to clean the throttle body.