Engine runs rough when cold.

2000 GMC YUKON
150,000 MILES • V8 • 4WD • AUTOMATIC
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THEODORE WILLIAMS
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  • 1 POST
My 2000 Yukon XL with 5.3 runs rough when first starting in morning. Clears up when warm. I've had new plugs, wires, and injection service. It has 150,000 miles on it. I purchased it new.
Jan 10, 2011 at 4:09 PM
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JDL
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  • 16,098 POSTS
If you have electronic throttle control, note the bulletin below. Also, check if the problem clears when it goes into closed loop. A coolant temp sensor can also cause issues?

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Jan 10, 2011 at 4:54 PM