grey smoke from exhaust

[Dr.Doom]

recently i let my buddy drive my car while i was driving behind him and i noticed that evberytime went full throttle, grey smoke came out of the tail pipe.

What causes that? worn rings?

[240sx_sr20det_12]

well more then likely all it is is incomplete fuel combustion....witch is no big deal or your ignition timing could be off. blue smoke is something to be concerned about.

[IanS]

well more then likely all it is is incomplete fuel combustion....witch is no big deal or your ignition timing could be off. blue smoke is something to be concerned about.

Not so much.

Unburned fuel is usually black. Oil burned in the combustion chamber will smoke blue, but oil dumped into the exhaust by leaking turbine seals will smoke gray.

Check to make sure the oil drain on your turbo isn't plugged or kinked. A plugged oil drain will over pressurize the CHRA, which results in oil pushing past the turbine seals into the exhaust, and in extreme cases, into the charge piping.

[BoredDSM]

Not so much.

Unburned fuel is usually black. Oil burned in the combustion chamber will smoke blue, but oil dumped into the exhaust by leaking turbine seals will smoke gray.

Check to make sure the oil drain on your turbo isn't plugged or kinked. A plugged oil drain will over pressurize the CHRA, which results in oil pushing past the turbine seals into the exhaust, and in extreme cases, into the charge piping.

c

I always thought black smoke was oil burning and white smoke was antifreeze burning. Correct me if I'm wrong. If you burn oil it usually is black smoke.

[IanS]

c

I always thought black smoke was oil burning and white smoke was antifreeze burning. Correct me if I'm wrong. If you burn oil it usually is black smoke.

Coolant will burn white

Oil turns diferent colors depending on the temp its burned at

If its burned with fuel in the combustion chamber, it will be blue, but if it just cooks on the walls of the exhaust piping, it smokes gray

unburned fuel will look black

[Dr.Doom]

cool cool, thanks guys, i'll look in that direction