You can purchase special spray, "throttle body cleaner", in any auto parts store. All necessary instructions are on the bottle.
Remove it, and throttle body carbon cleaner. Make sure that the valve can be moved easily.
Clean the throttle body.
Purchase a can of throttle body cleaner and follow the directions on the can.
Clean the throttle body with a spray throttle body cleaner.
Use the fuel brake cleaner or throttle body cleaner.
On the throttle body.
Where is the ECU on a 2002 Dodge Grand Caravan
The Trailblazer has an electronic throttle (drive by wire). There is no IAC valve, it is built into the throttle body. Remove and clean the entire throttle body.
It should be in the valve cover, there is a little hose connecting the valve the the throttle body.
The thottle body is connect to the plantum right in front of the air filter housing the throttle cable is connected to it.
I would check the air filter first. If the filter is clean you need to clean the throttle body.
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