I just had this problem on my 2004 Colorado. The Idle Actuator control motor on the throttle body was bad. Cost $160 for the part.
There are several things that can cause your 2004 Chevrolet Trailblazer to idle rough. The most common causes are a dirty fuel filter or a dirty air filter.
My 2006 Colorado had the same message shortly after I bought it. It turned out to be a short in the throttle body.
Check the Cats have not disintegrated.
I had the same problem with my 2005 ford expedition... it was my chamshaft....... The repair is expensive... But it fixed the problem......
I have a 2004 gt that has also developed a rough idle also and can't find the problem.... I wish you had the answer....
Colorado and Company - 2004 was released on: USA: 2004
The Season Colorado - 2004 was released on: USA: 20 August 2004
The 2004 Chevrolet Colorado has 16 valves.
The 2004 Chevrolet Colorado is a gas-powered vehicle.
The 2004 Chevrolet Colorado has an inline 4 engine.
The 2004 Chevrolet Colorado has a 5-speed manual.
The height of the 2004 Chevrolet Colorado is 5 ft. 4.9 in. (64.9 in.).