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Q: Rough idle and loss of power during acceleration. What could it be?

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Car has rough idle shop says tune up is needed. I change wires and plugs and even coil pack. But it still has an issue with the idle and even stalls

My car has 168000 miles.
My car has an automatic transmission.

A: This may be a sign of a dirty or failing id...

This may be a sign of a dirty or failing idle air control valve. This is a unit that reads the air intake into the motor as it is mixed with fuel prior to being injected into the motor. The computer takes this information and then adjusts fuel accordingly. When this is not working properly, it may cause over-fueling or under-fueling depending on the conditions.

I would recommend having an expert mechanic, such as one from YourMechanic, come to your location to perform an inspection to determine why the idle is rough and replace your idle air control valve if necessary.

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