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Q: rough idle

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it doesnt want to idle when its first started when the motor is cold, then after it warms up it will idle it will idle but a rough idle and when im sitting still its loping, like its getting to much gas and i also smell gas. i have already changed the spark plugs and spark plug wires and the filter is good.
My car has an automatic transmission.

A: These engines had a bad problem of getting ...

These engines had a bad problem of getting excessive carbon build up on the valves that causes this problem. You may need to have the intake system cleaned out more than once using a combustion chamber cleaner. Be sure to clean the fuel injectors as well. Once this is done, the fuel pressure should be checked to make sure it is correct and not leaking. If it is, then it may be a defective pressure regulator. I’d suggest getting some assistance with this by having a certified technician, such as one from Yourmechanic, to help diagnose your rough idle and fix it accordingly.

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