Q: Engine sputtering

asked by on October 06, 2016

When turning on the car, the engine starts sputtering. Little grey smoke coming from exhaust. What might be the problem with my car?

My car has an automatic transmission.

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Hi there, thanks for writing in. There are a lot of possible causes of this. Most of the time it is caused by a fuel system issue. When you get smoke like this it is usually caused by excessive fuel entering the engine. It may be a bad fuel regulator, a leaking injector, or even a bad sensor. If an oxygen sensor is reading wrong this can occur. I would usually scan the computer for codes to see if the computer has identified any problems. If not then I check all of the sensor readings with my scan tool. If nothing shows up there either then I check the fuel system for any leaks that are internal. If you would like help, consider having an expert automotive technician from YourMechanic come to your home or office to inspect and diagnose this sputtering and smoke issue for you, and make or suggest any repairs as needed.

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