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Q: Hesitation, stumbles, and sometimes stalls when accelerating

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I am having a problem with bad idle, hesitation, and stalling. I have tuned it up twice in the past year. New plugs, wires, caps and rotors, air and fuel filters. I also changed the upper wire harness and had the injectors cleaned. What is strange is I just changed caps and rotors and spark plugs and the car ran fine for about an hour. Parked it and the following weekend started the car with the same symptoms. I also had changed my EGR valve and swapped my throttle body but no change. I would really appreciate some help here. The car is in pristine condition but I can't enjoy it. Thank you.

My car has 91000 miles.
My car has an automatic transmission.

Hi there, thanks for writing in. It looks as if you’ve covered almost all of the bases. The only thing that I could think of without being there to complete a diagnostic inspection is that perhaps the idle control valve is stuck or needs to be replaced as well. It could also be a vacuum issue. Before you decide to purchase any more parts or keep chasing the issue, you might want to contact one of our local mechanics to help you accurately diagnose the issue. Here at YourMechanic, we can have a technician come to your home or office to inspect and diagnose this issue for you, and make or suggest the necessary repairs.

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