Squad... I'm sorry. I've searched probably every post on this forum as well as BLT posts on other forums and there is just so much random information floating around that I wanted to attempt to get some solid answers and hopefully edit this into a how-to. The one we have is good, but for noobs like me... it left something to be desired (likely because of the misinformation floating around elsewhere).

So perhaps some of you can help answer some of the questions.

1. When you disconnect the entire intake system from the turbine inlet, do you leave the BOV/DV on the UICP (in a stock system) and disconnect it from the intake pipe? The BOV/DV is obviously a source of leaking in some cars, so I would think it needs to be on the UICP with its hose attached. But then the one end of the BOV/DV is just left off in space... is that correct?

So UICP, then the BOV/DV pipe, then the BOV/DV is attached directly to the intake pipe (but obviously we've removed the intake pipe now).

2. Top Dead Center. I understand how an engine works. Some people have suggested that if your vehicle has some of the exhaust valves open, you will just bleed the pressure out through the exhaust? Whether this is true or not, does the motor need to be at TDC? Is there a circumstance where your engine and turbo system are in perfect shape (no leaks) and no pressure is able to be made? Also... fwiw, if anyone feels like telling me how to rotate the crank (and how it's accessed (through the passenger wheelwell?)) using tools, that would be great.

3. Engine "pressurization". As far as I've been able to tell... there is one hose that needs to be taken care of. The hose going from the drivers side valve cover, to the intake hose. This hose needs to be plugged? Or routed away so you don't hear it leaking or what? I've also heard that you should take your oil cap off to PREVENT the top end from sealing up?

In short, my car runs and boosts fine as far as I can tell, but I can't run any pressure into my system when boost leak testing. So I'm confused, and instead of just trying to find out who's right and who's wrong through trial and error... I figure I'd just ask and maybe try and help people out in the long run.

 

1. Yes you leave the bov attached and if you eliminate your entire intake system and test right from the turbo itself it eliminates #3 since you are removing the line that leads to your valve cover so it will not pressurize the crankcase.

Basically if you remove your intake from the turbo that is all that is needed to be removed since it never sees pressure. Everything else you leave alone. And I have never done a boost test and put the engine at tdc I've always just removed the intake and went at it and never had a problem this one is new to me I've never heard that it needed to be at tdc.

 

Remove intake from turbo,keep everything connected,BOV etc.

Attach your pressure adapter, NOTE: best to use an air compressor with a regulator set to 10 psi to start. Work your way up from there.

You will always bleed down air no matter what TDC or not as if the TDC on #1 is not on the others due to overlap on the cams, so throw the TDC thing out the window.

Get yourself a spray bottle filled with soapy water because you will never hear a slight boost leak. Spray all the connectors you want, you'll see bubbles if leaking.

Block off the hose at the turbo outlet also (depends on set-up)going to the boost controller or solenoid valve.

 

There are a number of threads suggesting TDC. Or to rotate the crank until pressure starts to build at least...

 

That makes sense... I'm hearing either a HUGE leak coming out of my j pipe area or going through my exhaust or something isn't right.

The TDC thing is busted then... what about the others?

 

^mine always holds pressure when I don't put it at tdc

 

Common leaks are the connectors for the LICP, the UICP, the recirc if bad, and the throttle body seals.

Mine was the seals, amazing how much boost/hp I was losing thru such a small seal.

 

Anyone have any thoughts on #3? I was doing more testing tonight and air was definitely coming out of the hose that comes out of the drivers side valve cover and goes into the intake pipe?

 

As far as #3 goes, (if I understand it correctly) no air should leak here as long as your PCV valve is good. Try pulling the PCV valve off the valve cover and see if it's leaking.

I think I may have this problem too... I'll be checking mine this week. It definitely feels like it lost it's snap, but I may just be used to it.

 

If you remove ur intake you are essentially eliminating the need to worry about #3 as stated before since it attaches to the intake.

 

Right, but at some point I'm going to want to test the "entire system" correct? Or should I only be worrying about everything from the turbo to the throttle body?

Once I had everything hooked up to the throttle body (ie, like normal) I noticed that I was getting air coming out of the hose on the drivers side valve cover that would normally go to the intake pipe (sorry I'm trying to be specific for clarification). So obviously the top end valvetrain is receiving some air.

1a. Is this all just blow by?
2a. Is it bad?
3a. Should it happen?
4a. Should I plug this to complete the boost leak test? Ultimately pressurizing the valve cover?

I mean... obviously Mitsubishi knew that it would be pumping some air out of it because its routed back into the intake... so I can't think it's "bad"?

 

Nothing on that? ^

 

You can cap the hose from the intake manifold to the pcv valve.

 

Also typically how long does it take to pressurize the system? I've been doing my test with soapy water and it (seems) to be leak free, but it takes probably a solid minute or minute and a half to pressurize? Using an 11 gallon 2 HP tank (125psi max)...