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Q: Car runs rough and eventually stalls when idling or at traffic lights

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When they car is first started, it runs good once they engine has warmed up it starts to sputter and , if they accelerator is not toyched...it will stall, Before it stalls, it acts like it us being choked out, By that I mean then engine sputters, then car rocks, it sounds like it is missing I have done a complete tune up changing the plugs, wires, distributor and the cap; changed the EGR temp sensor and blown out the Mass Flow with MF cleanerand it still runs terrible If I shift into neutral at a stop sign or traffic light, it will not run as bsd..,but still acts like it is not getting air or gas, a I don't know what else to do.

My car has 136000 miles.
My car has an automatic transmission.

Your stalling problem may be due to a vacuum leak in the engine, but one that only when it is warmed up. This would lead me to believe there is a possible problem with the EGR valve and its intake tubes. The EGR may be held open at idle from excessive back pressure from the engine not releasing the feedback valve.

The EGR back pressure transducer may be bad or the engine exhaust catalyst may be partly clogged, but I would say the transducer should be replaced first. Try to check to see if the EGR valve is partly open when this problem is happening. If you need help with this, a certified mechanic, such as one from YourMechanic can come to your location and diagnose your car’s stalling issue for you. From there, they will be able to make any repairs that are appropriate to resolve the problem.

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