Q: Idle jumps up and down

asked by on February 04, 2016

When I start the truck, the idle jumps up and down and then sounds as if it wants to shut off. Sometimes it will cut off when I'm at a light, and the Check Engine light comes on.

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Hello. If the Check Engine Light is coming on, then the first thing that would be helpful would be the computer codes. These can be retrieved with a scan tool. A mechanic would scan the computer first to get these codes to see what the computer is seeing as the problem. It sounds like you may have a faulty air flow sensor or you might need to have the vehicle tuned up. It may also be a faulty vacuum hose on the engine allowing air to enter the engine unmetered. If you do not have a scan tool to check the computer then I would enlist the assistance of a certified mechanic that can diagnose your Check Engine Light and move forward with repairs for your idling issue.

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