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Q: My car sputters when cold but idles smoothly after warmup - 2003 Chevrolet Express 3500

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Theres not much to describe. My starts to sputter a little when it is cold after startup and then runs smooth after it warms up. I tried cleaning the mass air flow sensor but that did not do much.

My car has 110000 miles.
My car has an automatic transmission.

A: Hi there. Beyond the MAF sensor, in most ca...

Hi there. Beyond the MAF sensor, in most cases, an engine that stumbles when it’s cold is caused by one of three different components: clogged fuel injectors, a dirty throttle body, or an EGR valve that is damaged or also dirty and needs to be cleaned. The best way to diagnose this issue is to clean all three components first and see if the stumbling issue goes away.

If not, I recommend having a professional mechanic, such as one from YourMechanic, complete an inspection to determine why the car is sputtering and suggest the necessary repairs.

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