Q: Check engine light and trouble starting.

asked by on January 25, 2017

My Malibu recently started showing a check engine light with the code P0172. We live in Florida and most mornings the car has trouble starting since it's cooler than usual. But on warm days when it has trouble starting there will be a huge puff of white smoke once the car starts. What options do you think my remedy the issue? Thanks!

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Hi there. The P0172 trouble code indicates that there is too much gasoline being detected in the exhaust gases exiting the combustion chamber. The ECU uses a number of instruments, such as the mass air flow sensor (MAF), oxygen sensors, and manifold absolute pressure (MAP) to monitor the air-fuel ratio of the engine; and any one of these components can be the cause of the rich situation. The puff of smoke is most likely raw fuel that can’t burn in the combustion chamber (or emissions). You might want to have a professional mobile mechanic complete a car is hard to start inspection so they can determine what is causing this issue and recommend or complete the repairs at your location.

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