Q: Why is my car idling on and off??

asked by on January 16, 2017

Though I have serviced recently, used Bosch super4 instead of usual super2, my car idling is inconsistent. Sometimes it even miss fire. I have changed throttle control unit but problem persists. Changed Airflow unit earlier.There is soot on the exhaust as combustion is definately incomplete. High rev count produces cricket like smell coupled with banging sound though not that loud. What could be the problem all of sudden?? I'm used to seeing water coming out of its exhaust pipe and smooth idling. please help.

My car has 97000 miles.
My car has an automatic transmission.

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