drivability issue? update 8-6-08 with videos of how fast it boost leaks

[Vicious_mole]

I have been having some issues feel like drivabliity. some symptoms

- car feels like it takes alot of throttle to move when cold
-car idles cold at 800-900 rpm and idles rough vac at about 12, idles high when warm about 1500-1200 vac at about 20, and the a/f seems very lean when its cold
-sometimes i get alot of knock when in vac going down the road at a steady speed

could a boost leak/vac leak cause all these or knock sensor ???

if any ideas where to look when loggin on link to give me any idea where it would be off, like what should the timing be at cruize? slft ltft? ect where should i look?

 

[viprez586]

Sounds like symptoms of boost leak and a bad ISC possibly.

Spray down all your connections with soap+water, don't forget injector seals and the compressor housing(the o-ring deteriorates sometimes).

You can test your ISC by following the instructions via vfaq.com

 

[quick_dsm]

worddd....does sound like a leak...do a test and let us know if that was the problem

 

[Vicious_mole]

worddd....does sound like a leak...do a test and let us know if that was the problem

well did a boost leak test, got a very very minor leak at the bov gasket, and now the only thing that leaks is the boost controler? from what i understood was that it bleeds off a litttle presure so the turbo would spool quicker but who knows but other that that no leaks what so ever, but i havent but the car back together yet to see if it made any differance

 

[Vicious_mole]

http://www.dsmtuners.com/forums/newbie-forum/298194-boost-leak-test-leak-out-bov-recirc-tube.html

Seen this earlier, wonder if thats whats leaing on my bov? have authentic greddy type S so ill have to go home and check this, now how bad of a boost leak will cause something to hesitate and what not, ### mine is just slight leaking, you can barely hear it leaking

 

[Vicious_mole]

alright, went and finished boost leak testing the car, found the top screw on the bov leaking, so i took it apart looked at the diaphram looked good not holes. so i tool and sealed the adjustment screw with some teflon tape and leaks gone. now the only leak to be found is from the pcv vent, leaks with the pcv hose hooked to the pcv valve and without it hooked to the pcv valve and caped off???

videos of how fast it leaks are posted
from full boost

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from low boost

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where should i look ? internal motor, turbo? somehow boost is getting into the crankcase ??wtf!

 

[Vicious_mole]

so i did a leakdown test today, found #1 good 0% loss and 2,3&4 at about a 20% loss, so i put some oil into the cylinders to seal the rings and found 1,3&4 at a 0% loss and #2 at a 10% loss hearing noise in the valve cover, so i suspect light ring wear on 23&4 but it showed green on the gauge i used and then slight valve seal issue in #2??? what you all think run it till it gets worse?

 

[VETTE_50_TH]

Did you hear any hissing from the intake, intercooler pipes, or anything. Those are the simplest to find.

James

 

[Vicious_mole]

Did you hear any hissing from the intake, intercooler pipes, or anything. Those are the simplest to find.

James

nope the only hissing during the boost leak test and the cylinder leak down test were out of the pcv vent on the side of the valve cover, minus the slight hiss in the vavle cover when i tested #2 thats y i suspected valve seals in the cyl