Q: Car stalling at first start, black smoke from exhaust

asked by on August 30, 2016

I've had troubles with my car stalling out, when I first try to start it in the morning with the engine is still cold. I went to the dealership several times with no answer to why this keeps happening. Now, I've noticed that there is a huge amount of black smoke coming from the exhaust. What might cause this? What kind of repairs can I expect?

Hello. There are a few possibilities for why your car is stalling when you first start it. Your car’s coolant temperature sensor could be sending the wrong information to the PCM, which will cause the PCM to send the wrong amount of fuel to the fuel injectors. It is also possible that the mass airflow sensor is sending a false reading to the PCM as well.

The black smoke from the exhaust could be due to oil leaking onto the spark plug tubes and then being burned by the engine. If this is so, replacing the valve cover gasket and oil tube seals should solve that problem. Have a certified technician, like one from YourMechanic, come and complete a diagnosis in order to determine why your car is stalling first before proceeding with replacing any parts.

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