Smoke

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K

King

I have A 94 850 turbo I had just replaced the turbo possibly due to a
misdiagnosis but that's beside the point. I had smoke coming out of the
exhaust if the car sat idling more than 5 min....If I rev the engine up
after idling I get a huge puff of smoke. The smoke clears up after a couple
of minutes of driving. I was originally told that it was the turbo so I had
the turbo changed.... I noticed an increase in power but the car still
smokes when idling. The smoke clears up after a couple of minutes of
driving. The car has 300000K and other than that the car is in mint
condition ....
What to fix next???? Kingsley
 
King said:
I have A 94 850 turbo I had just replaced the turbo possibly due to a
misdiagnosis but that's beside the point. I had smoke coming out of the
exhaust if the car sat idling more than 5 min....If I rev the engine up
after idling I get a huge puff of smoke. The smoke clears up after a couple
of minutes of driving. I was originally told that it was the turbo so I had
the turbo changed.... I noticed an increase in power but the car still
smokes when idling. The smoke clears up after a couple of minutes of
driving. The car has 300000K and other than that the car is in mint
condition ....
What to fix next???? Kingsley
Click to expand...

Blue smoke or black smoke?
 
King said:
I have A 94 850 turbo I had just replaced the turbo possibly due to a
misdiagnosis but that's beside the point. I had smoke coming out of the
exhaust if the car sat idling more than 5 min....If I rev the engine up
after idling I get a huge puff of smoke. The smoke clears up after a
couple of minutes of driving. I was originally told that it was the turbo
so I had the turbo changed.... I noticed an increase in power but the car
still smokes when idling. The smoke clears up after a couple of minutes of
driving. The car has 300000K and other than that the car is in mint
condition ....
What to fix next???? Kingsley
Click to expand...
Our 85 765T was doing that sort of thing, but worse. After a few seconds of
idling it smoked (blue smoke) and it continued until I had been moving about
half a minute. The crankcase ventilation was at fault - crankcase pressure
was building up at idle and causing oil to back up in the turbo drain, which
spilled over into the exhaust. It must have been pooling there, which would
explain why it took a while to stop smoking once I got moving. It would also
explain the huge puff of smoke. That would be unusual if it were valve
seals, because the hotter manifold area wouldn't allow much pooling. Valve
seal smoking tends to be immediate; they don't fit the "smoke at prolonged
idle, clears when moving" pattern very well.

Cleaning the crankcase ventilation system - I had to replace one hose that
was packed with deposits, and wished I had a replacement oil separator
available - cured the smoking.

But now you have a nice, new turbo - 300000km is a full life for any turbo.

Mike
 
King said:
I have A 94 850 turbo I had just replaced the turbo possibly due to a
misdiagnosis but that's beside the point. I had smoke coming out of the
exhaust if the car sat idling more than 5 min....If I rev the engine up
after idling I get a huge puff of smoke. The smoke clears up after a couple
of minutes of driving. I was originally told that it was the turbo so I had
the turbo changed.... I noticed an increase in power but the car still
smokes when idling. The smoke clears up after a couple of minutes of
driving. The car has 300000K and other than that the car is in mint
condition ....
What to fix next???? Kingsley
Click to expand...

I **suggest** that valve guide seals **might** be the problem. A
**qualified** tech could better tell.
 
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