1987 gn smoking out talipipes

car95

New Member
Joined
Mar 23, 2013
I posted thread on engine tech not much but good response, 1987gn smoking out tail pipes on deceleration ONLY, does not smoke idling or under boost, installed new pcv no help, 70,000 miles on car owned it since 1988. Thanks for your help!
 
I would pull cold side after turbo plumbing and look for oil build up if you don’t find any on cold side then pull exhaust side to see if turbo seals are shot. Should be evidence of oil leaking into exhaust elbow. If you don’t find anything there then move on to compression/leak down test. Normally turbo seals will smoke when you have your foot to the floor. Do you have oil pressure gauge?


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I would pull cold side after turbo plumbing and look for oil build up if you don’t find any on cold side then pull exhaust side to see if turbo seals are shot. Should be evidence of oil leaking into exhaust elbow. If you don’t find anything there then move on to compression/leak down test. Normally turbo seals will smoke when you have your foot to the floor. Do you have oil pressure gauge?


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Thanks Scott for the reply, I really appreciate it! Car is in storage right now, no oil pressure gage but thanks for a place to start.
 
Scott, I hate to show my ignorance but I would have to look and my car is at a different location/ Thanks for the help!
 
Could be valve seals?

I have a similar problem but smokes after driving, either hard on boost or not, puffs smoke at idle.
No smoke at accel or decel.
Plugs and turbo cold side are ok
No oil on exhaust side
Could it be the pcv?
 
do a leak down test . it will tell you where u are leaking . could be your valve stem seals r shot . as well as numerous other things
 
1987gn smoking out tail pipes on deceleration ONLY


Actually it might be smoking all the time. It's just not noticeable when you're diluting the smoke with much more exhaust.

Typically smoke on decell is oil going down the intake guides and/or up past the rings during massive amounts of vacuum. That's on manual N/A engines downshifting from redline....


In this case, there's plenty of thing to check. First pull all 6 plugs and see if one of the kids are doing their own thing.

Then look in the intake to see if the PCV is an oil injection device or if there's one oddball oily port.

If everything is dry, check the downpipe to see if the turbo is oil cooling your exhaust.
 
Actually it might be smoking all the time. It's just not noticeable when you're diluting the smoke with much more exhaust.

Typically smoke on decell is oil going down the intake guides and/or up past the rings during massive amounts of vacuum. That's on manual N/A engines downshifting from redline....


In this case, there's plenty of thing to check. First pull all 6 plugs and see if one of the kids are doing their own thing.

Then look in the intake to see if the PCV is an oil injection device or if there's one oddball oily port.

If everything is dry, check the downpipe to see if the turbo is oil cooling your exhaust.
 
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