Q: Black smoke pouring from exhaust

asked by on February 28, 2017

I have just started my car this morning and the weather is -6 and the car thankfully started first time within 2 seconds which was good unfortunately i noticed a big puff of black smoke coming from the exhaust which lasted for about 5/6 seconds then went away what could the issue be? My car is a ford Sierra and has only done 4900 miles and has recently been serviced before christmas

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Black smoke coming from the exhaust is usually an indication of a rich fuel condition. When this happens, this can be the result of many things such as faulty fuel injectors, a failing mass air flow sensor or a faulty fuel pressure regulator allowing too much fuel to be supplied to the combustion chamber to be burnt. When this happens the result is an excess amount of unburnt fuel being passed through the exhaust coming out in the form of black smoke. I would recommend having an expert from Your Mechanic come to your home to diagnose your fuel system.

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