Boost issues...wtf

[johnmarines]

hey guys/gals...I am having a problem with my boost that I cannot figuare out... I just recently switched over from a evo16g turbo internally wastegated running 25psi of boost to a hx35 external tial 38mm wastegate and for some reason I cannot boost over 10-12 psi max. I have tried switching vacuume sources and a new MBC I bought yesterday but still no go... Anyone have any ideas of whats going on? Like I said I didnt have any issues with my internally gated 16g. I did a boost leak test and corrected most of the issues except the seal that in my throttle body... which was there when I had my 16g. Here is a picture of my egine bay so You can see the way the lines are ran. Any ideas would greatly be appreciated.

 

[v8s_are_slow]

Can't see too well with the numbers on the picture. If I remember right, you need to have the vacuum line at the other port on the wastegate. What spring pressure are you running? Is the boost controller hooked up the same way as you had it on the E16g?

 

[johnmarines]

Can't see too well with the numbers on the picture. If I remember right, you need to have the vacuum line at the other port on the wastegate. What spring pressure are you running? Is the boost controller hooked up the same way as you had it on the E16g?

I have never had a tial before so I'm not quite sure if its hooked up correctly...There are two ports for vacuume lines, one is on the side (which is where I currently have it hooked to and the other is on the top. Should I connect it to the top? the spring rating is .9bar 13.05 psi, (which was on the invoice when I bought it new and yes the boost controller is hooked up the exact same way .

 

[v8s_are_slow]

Try changing the port. I believe you have it hooked up to the wrong one. The one you're using is the one that's used in conjuntion with the other port with some electronic boost controllers.

 

[Blaze2gDSM]

On tials the top nipple should always be left vented to atmosphere. I would suspect your problems lies somewhere else. Any leaks Pre Turbo? I have never seen the boost controller hooked up to the throttle body like that I would move it to the lower intercooler piping and see if that helps.

 

[aero_sallee]

Is the sealing/fire ring properly installed on the valve?

The sideport is correct.

 

[v8s_are_slow]

Yeah, I guess I had it backwards. Sorry.

http://www.tialmedia.com/documents/w3_tial_wginstall.pdf

But yeah, I didn't notice it was at the throttlebody. Even still, I'm wondering why you're not getting more boost cause if anything, you have it fully opened. If you get infinite boost, you have a leak in the vacuum line to the wastegate but you have an opposite problem. Almost as if you're getting boost pressure to the wastegate at all time. I second moving that line from the throttle body. Then let us know if it doesn't work.

Also, if that still doesn't fix it, try disconnecting to the line to the wastegate just to make sure it's not stuck open. If you still can't get more boost by disconnecting the line, you have a problem with the wastegate.

 

[DirtyBirdRacing]

Are you running the correct springs in your external wastegate?

Bill

 

[techghost]

Guys,
I'm facing the similar problem just after upgrading to a 3076. My turbine housing was big (1.06ar) so i'm changing it first; lets see if that resolves the issue.
This is very confusing...i'm keeping a close eye on this thread as well, might face the similar issue

 

[JFZERO ECLIPSE]

I'm saying he might have some boost leaks....

When using a MBC its best to keep the lines as short as possible and have the port for pressure as close to the turbo as possible...

Any way you can adapt a barb fitting to any of your pipes for a closer pressure port?

 

[techghost]

Did you get this issue sorted out?

 

[91Bomb]

Just built a boost leak tester and cannot build more than 5 lbs. Car is bone stock and was boosting fine untl a few days ago. Car does boost to 10-11 lbs in 2nd + 3rd gears momentarily and then it stutters/breaks up real bad until letting off boost. In 5th gear on highway it only goes to 5 lbs which no doubt explains 5 lbs max on leak test but CANNOT hear or see any conspicuous leaks even with spraying soapy water. Connected tester to turbo inlet and to throttle body with same 5 lb result and just realized I forgot to open TB plate on both tests so guess I screwed that up. But does the test from turbo inlet with throtte plate closed and only getting 5 lbs tell me anything so far because it doesn't even hold the 5lbs before dropping right back down to 0 after air compressor is turned off. This was my 1st boost leak test ever so please lmk if I'm doing something wrong, thanks.


*edit

Not trying to hijack thread and thought I was starting a new one

 

[JFZERO ECLIPSE]

Well if its dropping to 0 as soon as you disconnect the air line you have a major leak....

Heres an example with my car....

Completely rebuilt motor, every single gasket is brand new....took car for a drive a few times...felt like shit...

Did a Boost leak test wouldnt build any boost at all......btw its easier to have a clip on style air valve that stays on the valve leaving your hands free...my piece kept pushing air in as I sprayed for leaks...I found 2 leaks...when my blt was on the turbo, it wasnt fully connected to the turbo thanks to a water line being in the way...16g swap on my 2g....put a bigger coolant line on now its fixed....Now I'm getting like 1-2 psi in my intake tract...

I found a major major boost leak at the gaskit where my j-pipe connected to the turbo....pulled gaskit off...rtv sealant the crap out of it....went inside to let it cure for an hour....went back out, but its still leaking, but gauge went up to 4 psi woohoo...progress....well it was still leaking from the gaskit so I just kept tightening the bolts and the gauge quickly rose up to 20 psi yay...pressure....

Next thing you know my boost leak tested decided to seperate from its coupler...but I say I dont have any more leaks ...held 20 psi for 15 minutes before it blew apart...

 

[91Bomb]

Thanks, by J-pipe do you mean DP? Didn't occur to me about exhaust mani gasket + DP.

The good thing is car still runs fine except for racing around which I don't NEED to do for the time being. What did me in was a very breif highway race with a Cadilac Escalade

 

[2gGSXEclipse]

I think he means J-pipe as the pipe coming off the turbo and going to the intercooler

 

[JFZERO ECLIPSE]

Thanks, by J-pipe do you mean DP? Didn't occur to me about exhaust mani gasket + DP.

If you ever seen 1 13g/14b/16g turbo they use j-pipes that connect the turbo to the rest of the intercooler piping.....

I run the punishment racing kit on my car and only about 1 foot or so from the turbo is a port that I'm able to connect my mbc to or just run it striahg tto the wastegate....

 

[johnmarines]

well my update is pretty bad... so far I have not figaured out the problem. I will recieve my new "red" spring for my tial 38mm wstegate, which once installed it should be at 18psi without a MBC. I am hoping the wastegate is opening early but from what I have read its probably not. I even have hooked up the side port of the wastegate to my boost source with the same effect, cannot boost past 20psi. I will be dropping the exhaust this weekend and taking it out to see if it could be a exhaust restriction ,but considering I have a 3" exhaust without a cat I doubt it.

 

[johnmarines]

Well new update.... after changing out the turbo to a new fp and going with internally gated turbo and swapped out BOV's its still not building past 10psi. I did several boost leak tests which held 25+psi! I disconnected the vacuume source from the wastegate but still no change. When I go WOT it seems I can hear air escaping but not sure. Any ideas on what I can do to solve this problem...it really sucks not being able to build boost past 10psi!!!

 

[BLINKY619]

Well new update.... after changing out the turbo to a new fp and going with internally gated turbo and swapped out BOV's its still not building past 10psi. I did several boost leak tests which held 25+psi! I disconnected the vacuume source from the wastegate but still no change. When I go WOT it seems I can hear air escaping but not sure. Any ideas on what I can do to solve this problem...it really sucks not being able to build boost past 10psi!!!

if your only making 10lbs of pressure... then im pretty sure you can hear it..!!!! specially by the way you say it that it leak quick as hell

 

[johnmarines]

I'm just not sure where I should look for it leaking. I would figuare the boost leak test would show the leak but at 25psi no leaks. I even removed the egr valve and replaced it with a block off plate with no change.

 

[pneumo]

OK so lets look for something else.
How does the engine run at WOT? Does it sound normal or does it misfire and sputter?
Have you checked the cam gears to make sure the timing marks line up correctly?
When does the turbo reach 10psi?

 

[johnmarines]

OK so lets look for something else.
How does the engine run at WOT? Does it sound normal or does it misfire and sputter?
Have you checked the cam gears to make sure the timing marks line up correctly?
When does the turbo reach 10psi?

The engine runs stronge at WOT, the only thing I seem to notice is that once it reachs around 5k rmps it starts to slowly climb to a higher rpm. I dont seem to notice any misfiring or sputter. I have double and trippled check my timing marks about 2 months ago but I will check them again this coming weekend. If I had to guess it almost seems like a blockage through the fmic but wouldnt this come up during the boost leak test? I am enclosing a log that was taken this afternoon on the way home from work. The boost est. is slightly off. its the v3 version. thanks guys for all the input.

 

[pj91gsx]

The engine runs stronge at WOT, the only thing I seem to notice is that once it reachs around 5k rmps it starts to slowly climb to a higher rpm.

i say its because if the leaking throttle body that your high rpm power is not there. Just go ahead and rebuild the throttle body. it cost me like 50 cent for the orings to rebuild mine, it works great!

 

[johnmarines]

i say its because if the leaking throttle body that your high rpm power is not there. Just go ahead and rebuild the throttle body. it cost me like 50 cent for the orings to rebuild mine, it works great!

I had the tb rebuilt in febuary by throttlebodys.com.

 

[johnmarines]

Finally after months of fustation this boosting issue finally comes to an end. After swaping almost every componet that Ive installed in the last 6 months I was at a lost. I finally decided to swap back to a stock intercooler thinking that my dejon was the problem... but guess what, NOPE . So as a final act of fustration I dropped my exhaust to see if maybe I had a obstruction. I unbolted the downpipe and wired it to the side and took it for a short drive. After I drove down my street I got on the main and went WOT for about 2 seconds and guess what, the boost shot up to 25psi! Talk about a relief!!!! After I get home I drop the exhaust completely and cut it open. When I cut a few inches from the flex pipe I looked in and saw it was only open about 1 1/2 inches. Damn ebay exhaust. Now I'm headed to the auto parts to pick up a new one and weld it back together.