924Board.org

malpaslane · Joined: 23 Mar 2008 Posts: 78 Location: wales, uk

Hi All, well i,ve enjoyed the last month driving the s2 turbo around, after taking so long to get it running with all the problems of a car that hadn,t run for about 4 years . She goes like a dream now, but (there had to be a but ) when the the car is left to idle in traffic or allow to get hot to the point where the fans kick in, she starts to smoke and if i rev her a little it clears, she also blows alittle smoke if i,m coasting down hills and not touching the throttle pedal,but not all the time,only after she,s been sat in traffic and gets hot, is this the turbo seals or something more . The car has bills for an engine rebuild about 10k ago by a good porsche garage. As always any help would be great , thanks Rik....
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931 1982, PAIN IN THE ARSE,BUT GETTING THERE. 911 1976 2.7. 931 1981 S2(NON RUNNER) ALFA 156 SPORTSWAGON.

jazz guy · Joined: 26 Nov 2002 Posts: 434 Location: Colorado

I'd say that the turbo seals could be leaking, but I have never had personal experience with that condition so someone else might be able to answer that directly . I would add leaky valve seals, and loose valve guides to the list of things to consider. Smoke during periods of engine vacuum can be a symptom of oil entering the combustion chamber from the top end. Though, if the head was rebuilt, that shouldn't be the problem, but stranger things have happened. Was the rebuild complete, block and head?

Cheers, Brian

Rasta Monsta · Joined: 12 Jul 2006 Posts: 11733 Location: PacNW

10k miles, but how much time? Unfortunately, valve seals don't like sitting. . .sure sounds like the right symptoms.
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Toofah King Bad

WeiBe (1987 924S 2.5t) - 931 S3

924guy · Posted: Thu Jun 12, 2008 11:08 am Post subject:

if it "clears" im more inclined to suspect a valve seal issue, though it also could be a turbo seal. do you have smoke on start up , especially after parked overnight and just after the engine gets to running temp? does the smoke increase exponentially with acceleration?
your description could be the beginning of a turbo going out, in which case it will get noticeably worse, sometimes almost instantly, sometimes over a long period of time. But I tend to think more its a valve seal problem.

On occasion, just a good running out will clear carbon deposits that cause the issues, give her a good run / work out perhaps you can blow out some carbon and improve your seals... if that doesnt help, id check the valves first..
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Eric
78 924
82 931 SE "smokey"
99' VehiCross
Y2K Honda Insight
http://www.cardomain.com/id/924Guy
Performance by Pasha

Paul · Posted: Thu Jun 12, 2008 12:54 pm Post subject:

Pull the intake pipe from the turbo to the throttle body and see if it is coated with oil.
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White 87 924S "Ghost"
Silver 98 986 3.6l 320 HP "Frank N Stein"
White 01 986 "Christine"
Polar Silver 02 996TT. "Turbo"
Owned and repaired 924s since 1977
Porsche: It's not driving, it's therapy.

Rasta Monsta · Joined: 12 Jul 2006 Posts: 11733 Location: PacNW

malpaslane · Joined: 23 Mar 2008 Posts: 78 Location: wales, uk

Hi Guys, thanks for all the info once again, to answer the questions, first paul, yes there is some oil in intake pipe, second 924 guy, not really any smoke on start up from cold and the harder i drive it the better it is, it only does it if i,ve sat in traffic and it gets hot or when it,s coasting down long hills and jazz guy, i,m not sure if the head was rebuilt , i,ll have to check paper work again and rasta monsta, rebuild was 1993 and hasn,t done many miles since and has been parked up for last four years going on the paper work i,ve got. many thanks Rik
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931 1982, PAIN IN THE ARSE,BUT GETTING THERE. 911 1976 2.7. 931 1981 S2(NON RUNNER) ALFA 156 SPORTSWAGON.