Loss of boost..Couple questions

[Jman9912]

Hey guys, i've got a few different questions, but they all really pertain to the same thing.

I've got a 98 GS-T with a 14b turbo, fmic, vibrant 3" turboback exhaust, turboxs boost controller, greddy bov

First off, I do not have the rubber ring that goes inside the stock intake pipe which connects to the turbo. (The rubber ring that goes around the turbo inlet to make the intake pipe fit correctly) So there wasn't a perfect seal around the inlet. I was going to take a hose or pipe and cut it down to replicate this piece, but could not find the right size. I took a coupler that came with my fmic and cut it down to fit tightly. Since I did this, my BOV sounds like it's laughing at me and sometimes while i'm under boost, I see my boost gauge drop rapidly. I don't necessarily think the turbo inlet piece I made has anything to do with this, I just wanted to let you know just in case.

I can boost leak test the car from the intake manifold but that's about it, because without the correct rubber piece, my boost leak tester doesn't fit and I can't seem to find the right size..I feel like i'm overlooking something.

This is actually the only question so far, once I get this figured out, I can rule out the other issues i'm having.

I tried to type this as straight-forward as possible without sounding like an idiot. I haven't had much sleep, so I apologize in advance. Any help would be greatly appreciated. If you guys don't get what i'm saying, feel free to ask questions so I can clarify.

 

[XiKeiyaZI]

You need to set your engine to TDC with the cam dowels at 12:00 and perform a boost leak test from the Turbo. It may help if you section it off into pieces, such as plug your charge piping after the BOV and testing the piping alone and then performing a separate test on the engine itself.

Make sure to soak all of your piping and couplers in soapy water before hand as this will help you determine where leaks are much easier.

The piping around the turbo, however, will not cause a boost leak. That's where it draws air in. It could cause a vacuum leak, however.

 

[JayB12]

The noise your hearing sounds like compressor surge, also if air can get in the turbo from that piece you fabbed your getting more air than the maf is reading causing a lean condition.

 

[Jman9912]

You need to set your engine to TDC with the cam dowels at 12:00 and perform a boost leak test from the Turbo. It may help if you section it off into pieces, such as plug your charge piping after the BOV and testing the piping alone and then performing a separate test on the engine itself.

Make sure to soak all of your piping and couplers in soapy water before hand as this will help you determine where leaks are much easier.

The piping around the turbo, however, will not cause a boost leak. That's where it draws air in. It could cause a vacuum leak, however.

I know all of this..You didn't read the post.....

I can't test it from the turbo right now. I have to find the right size pipe to make a new tester. I know it was creating a vacuum leak.


Jay, I know this as well. I fabricated that piece because it was BAD without it. There was a 1/4" of space between the inlet and the intake all the way around.

 

[XiKeiyaZI]

I know all of this..You didn't read the post.....

I can't test it from the turbo right now. I have to find the right size pipe to make a new tester. I know it was creating a vacuum leak.


Jay, I know this as well. I fabricated that piece because it was BAD without it. There was a 1/4" of space between the inlet and the intake all the way around.

Then you don't have a question to ask without the proper results when knowing what you need to do, correct? Sounds like you need to go get the correct piece that you need and perform that boost leak test before you move further.

Your issue is a textbook case of a boost leak. Perform the test, find the issue, perform the fix, have your resolution.

 

[honda_burner]

I know all of this..You didn't read the post.....

I can't test it from the turbo right now. I have to find the right size pipe to make a new tester. I know it was creating a vacuum leak.


Jay, I know this as well. I fabricated that piece because it was BAD without it. There was a 1/4" of space between the inlet and the intake all the way around.

ive got my stock intake pipe with that insert you need. if you want it pm me

 

[JayB12]

Go to home depot and make a boost leak tester. Here's a vid, should't take long.

Boost Leak Testing 101: Building the tool. - YouTube

 

[Jman9912]

Also...the car is overheating now...Just started. It's one thing after the other. I need to get this car straightened out. The person that had it before me didn't know wtf they were doing. I think I need to redo all of the lines and everything.

 

[JayB12]

Are you throwing any codes?

 

[red1993gsallmt]

pull the coolant cap while its running, if you see bubbles its a headgasket. can you do a compression test?

 

[rEclipserGST]

pull the coolant cap while its running, if you see bubbles its a headgasket. can you do a compression test?

If it is bubbles, could be the coolant system wasn't bleed properly. Could be a pin-hole in a coolant hose. How is your coolant overflow looking? When was the waterpump, radiator cap, thermostat, coolant temp sensor, or coolant replaced?

Buy the correct size you need. I used a coupler from old intercooler piping. Works perfect on my ebay intake & mhi 14b.

Pressure tester would help with figuring out your overheat issue. Or just boil the thermostat.

 

[kennyg]

Is it possible the Greddy BOV is not holding properly? Don't they have to be adjusted to the amount of boost you're running, by using different springs on the Greddy's?