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#1
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Strange PPI Results
This is on 2004 GT3 with 45K miles and 0 range 2 Over revs which would indicate missed shift. It is 2 owner car, and owned by the current owner since 2008 (about 17K miles), and has been primarily a track car, and in a very desirable condition with fresh suspension, and many services up to date. I am not willing to walk away from the car yet, but the fact that one entire side seems to show "something" is very strange.
All cylinders have very minor scoring. Compression test: Cyl. 1 = 151 , 2 = 150 , 3 = 150, 4 = 145 , 5 = 145 , 6 =146 . Leakdown test: Cyl. 1 = 4% , 2 = 5% , 3 = 5% , 4 = 19% , 5 = 20% , 6 = 19%. Check cam shaft deviation via tester. Bank 1 at -1.3. Bank 2 at -3.73. Additional usual checks to check for leaking valves and rings have shown no evidence of leak from either side. I have asked for hot leak down and waiting to hear. Any thoughts, ideas, or speculations? Nader
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Nader There are 3 sides to every story. Mine, yours, and the truth. 91 944 S2 - Mine, Sold 7? 914-6 Vintage racer - Mine 93 964 - Not mine 95 993 - Hers - Sold and will be missed 04 GT3 - ours? Doing double duties at DE, anyway 06 987 - Hers - plan to let son use for DE - My DIY A few others Last edited by N Fotouhi; 01-17-2019 at 09:18 AM. Reason: Added more information |
#2
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Well, if the rings and valves aren't leaking, the No 2 Bank cylinder numbers would suggest a head gasket leak.
Has an oil analysis and coolant analysis been performed? Quote:
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CT 83 911SC 12 Lexus CT 200h 08 Outback wagon 04 F250 SD Truth be it known, I just like working on cars - Slick Henderson |
#3
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Quote:
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78 SC, the 'Red Car' |
#4
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A leak down shows more than a %. You can often tell where the air is going. Did they indicate where?
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http://vimeo.com/29896988 “Those that can make you believe in absurdities can make you commit atrocities.” Voltaire. "There is grandeur in this view of life...." Darwin. The mountains are calling and I must go. “The earth has music for those who listen” Shakespeare. You Matter. (Until you multiply yourself times the speed of light squared. Then you Energy) “We’ve got lots of theories, we just don’t have the evidence’. |
#5
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The hot leakdown shows no difference.
After some checking and discussion, the hypothesis is that the differences may be an indication of differences in manufacturing tolerances between the two sides since there seems to be no mechanical indication. I am also told by a reputable source that it is not unusual to see such differences in varioram engines. If I buy and it blows up, I made the wrong call. Otherwise, it was nothing to worry about.
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Nader There are 3 sides to every story. Mine, yours, and the truth. 91 944 S2 - Mine, Sold 7? 914-6 Vintage racer - Mine 93 964 - Not mine 95 993 - Hers - Sold and will be missed 04 GT3 - ours? Doing double duties at DE, anyway 06 987 - Hers - plan to let son use for DE - My DIY A few others |
#6
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Thats a lot of leakdown deviation. Where was the air coming out? You can typically hear: Intake/case/exhaust.
Are they really on the compression stroke doing the 4/5/6 bank? (shop error?)
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Stephen www.salazar-racing.com 1970 914/6 - 3.0L GT 1983 911SC - 3.32L IROC 1984 930 2008 S2R1000, dirt bikes (some gas, some electric), Sherco trials bike Sold: 2001 Boxster (hers), 2003 996tt x50 , SpecE30, 1996 E36M3 GTS2 racecar, 2015 Mustang GT |
#7
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^!
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http://vimeo.com/29896988 “Those that can make you believe in absurdities can make you commit atrocities.” Voltaire. "There is grandeur in this view of life...." Darwin. The mountains are calling and I must go. “The earth has music for those who listen” Shakespeare. You Matter. (Until you multiply yourself times the speed of light squared. Then you Energy) “We’ve got lots of theories, we just don’t have the evidence’. |
#8
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I have no reason to think that the shop made an error since everything was rechecked over 3 days. There was no indication of leak from intake/case/exhaust. That is why the results are puzzling, and I have finally decided it may not indicate an issue.
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Nader There are 3 sides to every story. Mine, yours, and the truth. 91 944 S2 - Mine, Sold 7? 914-6 Vintage racer - Mine 93 964 - Not mine 95 993 - Hers - Sold and will be missed 04 GT3 - ours? Doing double duties at DE, anyway 06 987 - Hers - plan to let son use for DE - My DIY A few others |
#9
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http://vimeo.com/29896988 “Those that can make you believe in absurdities can make you commit atrocities.” Voltaire. "There is grandeur in this view of life...." Darwin. The mountains are calling and I must go. “The earth has music for those who listen” Shakespeare. You Matter. (Until you multiply yourself times the speed of light squared. Then you Energy) “We’ve got lots of theories, we just don’t have the evidence’. |
#10
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The air has to be going somewhere if it's leaving he cylinder. Did they listen? Where is the car located - perhaps a different shop... Mezger engine is supposed to be a tank--should tolerate a rebuild well but make sure the car is priced to allow for that (or mitigate the risk).
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Peter (not "Pete") K. 2016 Cayman S 1999 Miata ("SM") race car 2016 Toyota Highlander--tow vehicle/wife's DD 2017 VW GTI SE (DD) Gone and missed: 1992 Miata ("SSM") race car 2009 911 C2S Coupe 2004 Toyota Prius - sold to son's girlfriend 2006 Dodge Durango 2003 Acura MDX 86 Black 911 Coupe race car 86 Gold 911 Targa 82 WineRedMetallic 911 Targa |
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