03 Burb. Runs Rough When Cold

By ThorsHD
February 28, 2011 in Ask A GM Technician

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ThorsHD

Posted February 28, 2011

it is a 2003 suburban with a 5.3. it starts fine. it idles rough when cold and stalls. I have to keep the rpm up for 3-5 min... once its warmed up it runs great the rest of the day.

any help would be great,

thanks

txab

Posted February 28, 2011

Checked for any codes? Might have a temp. sensor out and the ecm doesn't know to go into open loop operation. Sometimes you can have an intake leak when it's cold, clears as it warms

ThorsHD

Posted March 1, 2011

Author

Posted March 1, 2011

there are no codes.

jro909

Posted March 1, 2011

fuel pump?

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