Q: rough idle when stop

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I have replaced the evap sensor, spark plugs, spark plug coils, gas cap, cleaned out the throttle body and the maf mass air flow sensor. The car runs roughly and its hard to pick up speed and power and when im at a red light the car shakes as if it wants to stall long as im moving weather or not its slow its fine but a complete stop and itll shake again. i also have the intake and exhaust camshaft position sensors to be replaced but I cant locate the old ones when looking at the engine. What can I do to restore power and stop the rough idle? 2006 chevy Malibu 4 cyl. 100K miles

My car has 101800 miles.
My car has an automatic transmission.

I would recommend using a portable scope to look at the secondary firing patterns which will enable you to narrow down the issue to fuel versus an ignition fault. The problem you are describing could be due to a faulty mass airflow sensor, throttle position sensor, faulty engine coolant temperature switch/sensor (typically at cold start only), inadequate fuel delivery or pressure (clogged fuel filter, injectors), contaminated or old gasoline, leaks in the EGR system, intake vacuum leaks, and so forth. If you request an engine stalling/rough idle diagnostic the responding certified mechanic will get this resolved for you promptly though. If you have further questions or concerns, do not hesitate to re-contact YourMechanic as we are always here to help you.

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