Mechanics

CHEVY ROUGH IDLE ONLY WHEN COLD

2004 Chevrolet Trailblazer

Engine Mechanical problem
2004 Chevy Trailblazer 6 cyl Four Wheel Drive Automatic 88684 miles

Hello... have 2004 Trailblazer EXT, 88K miles, no work done to motor other than oil changes. Engine idles very rough when cold, even stalls occasionally, but after a couple minute of driving (when warmed up) it runs just fine. Is this a sensor problem, and if so, which?


http://www.2carpros.com/forum/automotive_pictures/400662_114_2.jpg

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Mahoy78spyder
August 24, 2009.




Test the resistances on the coolant temperature sensor hot and cold, also clean out the idle air control valve.

GM Coolant temperature sensor

Temp Resistances

-40 100.7
40 7.5
100 1.8
210 185
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Tiny
Rasmataz
Aug 24, 2009.
Thanks for your blazingly quick response. I did a check on the IAC and learned that 2004 is the first year Chevrolet assembled it with the entire throttle body so it is no longer a separate component. I can see it visually on top there but don't see a way to clean it. Any suggestions?

Also, on the coolant temperature sensor. Where is it located exactly?

Tiny
Mahoy78spyder
Aug 26, 2009.
The coolant temperature sensor is located on left front of engine block near the alternator/generator as for the IACV you have to remove it form the TB and clean out-does yours looks like this


http://www.2carpros.com/forum/automotive_pictures/12900_IACV_2.jpg


Tiny
Rasmataz
Aug 26, 2009.

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