Boost Leak Test Help

[XtremeRIP]

I am having some major issues with building up boost or spooling not until 4500-5000 rpm in my talon. Ive read some forums and this may sound stupid maybe but im not sure how to test for boost leaks. I want to check for any boost leaks and not sure how really. Also my car is Automatic and i cant really build any boost pressure at all while in park or neutral I would appreciate any help. Also i always get confused between boost lag and boost creep what is the difference if someone could tell me.

 

[girlieracr4g63]

Go to Vfaq and look for the directions on making and using a tester. Its really simple and you use air from another source (ie..compressor or bike pump) to build the boost. Good luck!


wendy

 

[travislaw]

Start at the throttle body elbow, check for leaks in injectors seals, PCV, throttle BISS screw, throttle shaft O-Rings, and vaccum lines. Then once any leaks found are taken care of, test at the Intercooler on the intake side. Again look for intercooler leaking, connections leaking, the BOV gasket leaking. Then test at the turbo. Check for connection leaks, a well known one is the J-Pipe where the J-Pipe meets the turbo. Hope that helps.
It took me forever to find everything to make a tester, so if you want to buy an aready made one, here is a good site:
http://www.siliconeintakes.com/tester.htm

 

[girlieracr4g63]

Start at the throttle body elbow, check for leaks in injectors seals, PCV, throttle BISS screw, throttle shaft O-Rings, and vaccum lines. Then once any leaks found are taken care of, test at the Intercooler on the intake side. Again look for intercooler leaking, connections leaking, the BOV gasket leaking. Then test at the turbo. Check for connection leaks, a well known one is the J-Pipe where the J-Pipe meets the turbo. Hope that helps.
It took me forever to find everything to make a tester, so if you want to buy an aready made one, here is a good site:
http://www.siliconeintakes.com/tester.htm

Good info However it is posted a million times on here. Hence the reason for me sending him to Vfaq. As far as everything you need. The coupler and cap can be found at home depot or lowes. Clamps and valve stem at pretty much any parts store.


Wendy

 

[nuclearpenguin]

follow what they said on the boost leak tester.

turbo lag is when it takes longer to spool up the turbo (usually because you have a bigger turbo). boost creep is when your wastegate can't dump all of the pressure so your turbo spools up more than it's set to and you get more boost than what you set up for.

 

[XtremeRIP]

Thanks guys that boost coupler looks easy to make that will help a ton so i can at least be able to check with boost in the system. Is there any spots on the turbo or maybe my external wastegate i should check also?

 

[nuclearpenguin]

Thanks guys that boost coupler looks easy to make that will help a ton so i can at least be able to check with boost in the system. Is there any spots on the turbo or maybe my external wastegate i should check also?

i just pumped the air in at the turbo inlet then listened. the leaks should be obvious, your mbc will leak as well (but its sposed to ). up in the engine bay ,youll hear any leaks you have, just make sure to get down in the fender well and listen around the intercooler for any.

 

[XtremeRIP]

Alrighty guys i made the coupler and hooked it up but i cant seem to get pressure in the system. I am getting maybe a max of 2 psi in the system. I hear the MBC hissing but the pressure isnt staying in the system. Should i block off the hoses that were goin into the air intake hose that led to the turbo inlet? I feel a little air coming out of them but i wasnt sure if i needed to block those or not.

 

[zippyshoe]

Adjust your MBC to its maximum boost setting then run your boost leak test again. This may have been preventing you from building any pressure in your intake.

 

[Talesin]

Uh... no. The MBC just controls how much pressure the wastegate sees, with a very small bleeder hole to avoid pressure locking a ball-and-spring style unit.

 

[zippyshoe]

It looks like many posts on this forum recommend removing your MBC altogether when performing a boost leak test and substituting a single vacuum hose between your boost source (compressor housing, intercooler pipe, whatever your MBC is using as its boost source) and the wastegate actuator.

 

[oldman]

It looks like many posts on this forum recommend removing your MBC altogether when performing a boost leak test and substituting a single vacuum hose between your boost source (compressor housing, intercooler pipe, whatever your MBC is using as its boost source) and the wastegate actuator.

It looks like you're right.

 

[XtremeRIP]

I blocked off the mbc but im still unable to get pressure in the system.

 

[zippyshoe]

What are you using to provide the compressed air? If you are using a bike pump, you may not be able to build any pressure if you have a bad enough boost leak. You may need to use a compressor - just make sure you monitor the air pressure somehow so that you do not over-pressurize your intake.

 

[XtremeRIP]

I have a nice air compressor with plenty of air, and i have a friend watching the boost gauge which wont reach over 2 psi. Any ideas

 

[travislaw]

I have a nice air compressor with plenty of air, and i have a friend watching the boost gauge which wont reach over 2 psi. Any ideas

Start spraying soapy water. Do what I suggested as far as the order of where to test, it will help you find the leaks easier. Otherwise you could be looking forever.