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Q: Cold start

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I've recently cleaned my performance maf sensor, my cold air intake, and also changed my oil. When I start my truck in the mornings it wants to bog out. Sounds like its about to die then rpms go back up and down. I live in Colorado where it's 20-30 in the mornings. My trucls motor isn't even broken in yet. Only has 65,000 original miles. Please help

My car has 65000 miles.
My car has an automatic transmission.

As a general rule, car engines do not like cold weather and do not do operate as well in cold weather. When you start your car in the morning and turn the key to on, the coolant temperature sensor immediately reads the temperature of the coolant and relays this to the computer indicating that the coolant is cold. The computer then knows at this point that it needs to enrich (add more fuel) the air/fuel mixture at startup due to the change in air density. When you start the car, you will notice that it idles high for a period of time until the engine warms up. This is the enrichment cold start process. This is done with what is called a cold start injector which injects more fuel into the motor until the engine reaches a specific operating temperature. The computer simply feeds a little extra gas through the fuel injectors to start the engine and then maintains a certain amount of fuel supply to the motor until it is warm. I would recommend having an expert from YourMechanic come to your location to take a look at your vehicle and diagnose your cold start issue.

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