Hi,

I just did some trys to do find boost leaks, i attach my tool on the turbo inlet instead of the intake pipe. I can pressure test to throttle if i block the hose connector bevore the throttle. But if i set the complete system under pressure to find leaks on the intake manifold the air is comming out of my exhaust. Cranked the engine by hand in every postion but the air will allways come out of the exhaust.

Any ideas?

Forged 2.0 with hks 272 cams

 

Exhaust valves not sealing.

 

But compression was good before winter. And car is running... It's pushing ok for the current Boost.... But got the problem with flutter and high pitched sounds on wot after 4500rpm (3rd gear) with my atp gtx3576r... So wanted to start with Boost leak test first. But if the exhaust valves would not seal I would have bad compression and the car would not drive like it drive... (Cruise and idle is perfect, Boost with the described problem but smooth power output)

 

Run the engine and then check again. Maybe a valve was stuck.

 

Already tried 2 times.

Maybe the timing was not adjusted right on the camshaft and camgear install?
Is it possible that this is the problem but compression and drive ability is still good?

 

If you really want to know, have a leak down test done.

 

Still have the egr in the car? My bet is faulty egr stuck open causing the leak you're experiencing.

 

This, or one of the cylinders is in the overlap phase of the cams, and both the intake and exhaust valves are open.

 

No egr on the car.

Car was running with good power on fp green as i bought it, switched to atp gtx3576r and now the problem and my first boost leak tests do not work and i have the problem described above.

I will check timing next as i dont have the equipment for a leak down test yet... Or any other recommendations what to check?

 

this...^^^

i usually put close to tdc and then turn crank just a little more.
try it... if it wont build, turn crank a little more.

soon as you get it right, it will build and hold pressure quick.
(assuming you dont have a leak... then you could hear it)

 

turned the crank many times, and to all marks we could see on the camgears... allways the same

 

Mine was cured by removing the egr. Since that's ruled out in your case, try this to be sure you're not in overlap:

With one piston at TDC on the compression stroke the other piston is going to be at TDC of the exhaust stroke. That is right when you get valve overlap, i.e. both intake and exhaust open at the same time. So the air is going right out the exhaust valve.

When I do a boost leak I put a long extension in the #1 and #2 spark plug holes. Then manual crank the engine until they at the same height. This ensures that no cylinder is a TDC on any stroke, so you have no valve overlap. Then put the spark plug back in and do your test.

 

Did u do a leak down test?

 

do compression or leak down test. you might have a bent valve

 

If the throttle plate is closed, it should block 99% of the air coming in. What pressure are you hearing it coming out the exhaust?