Q: rough start, runs well, after it warms up

asked by on November 05, 2016

Has codes of po174, po420 & po340. When truck first starts, seems to want to "kill", unless given extra gas. Once truck warms up, seems to run fine. Any idea, where to start looking for the problem?

Thank you,

Roberta

My car has 169000 miles.
My car has an automatic transmission.

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