Q: After driving awhile, when idling, RPM drops below 500 & car stalls. Happens rarely but RPM fluctuates, and drops suddenly.

asked by on July 13, 2016

I drive my car around, and it is fine when driving, however I noticed when I am stopped at a red light, the RPM meter fluctuates and bounces up and down between 500 RPM and 1000 RPM. After about 15 minutes of driving, RPM drops and car stalls. Have to restart the car to fix the issue and be able to drive again. This only happens sometimes, why?

My car has 208000 miles.
My car has an automatic transmission.

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If you are having a stalling problem then you may have a computer code stored in memory. I suggest having the computer scanned to see if there is any codes stored and diagnose them as needed. The intake hose and air filter should be inspected for leaks in the hoses and dirty or leaking air filters. If the air filter is dirty or leaking then have the mass air sensor cleaned. If you still need help, have a mechanic diagnose the stalling issue for you and let you know exactly what repairs should be done.

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