This means that your engine is burning oil. The valve guide seals or piston rings are most likely warn out and the oil is leaking past where it should be lubricating. The oil is going to the combustion chamber where its being burned up with the fuel. Burning oil can cause rough starts as this can ruin your vehicles spark plugs.
If your vehicle is turbocharged it is also possible that the blower is in need of rebuilding or replacement.
There are many reasons for gray smoke:
- Fluid getting burned up in the engine
- Faulty transmission
- Vacuum modulator
Its best to have gray exhaust checked out by a trusted mechanic.
- This is probably the result of normal condensation buildup inside the exhaust system
- This can be caused by the engine burning coolant that can result in a serious issue like a blown head gasket, damaged cylinder head, or cracked engine block. These are all costly repairs.
This means the engine is burning to much fuel. You should check your air filter and other intake components like sensors, fuel injectors and the fuel pressure regulator.
It may also be a clogged fuel return line. Black smoke is very easy to have diagnosed. However, Burning unnecessary fuel will affect your fuel economy so make sure you get it checked out as soon as possible!
Any exhaust coming from your vehicle means it is in distress. Pay attention to what your vehicle is trying to tell you in order to ensure many years of adequate driving. Drive safe!