Turbo Problem

[whokilledhoughes]

well its been about 4000 miles since ive installed the turbo on the car...

where to start...well to begin with the car is only boosting 5psi...i thought ok i got a boost leak somewhere....did a boost leak test like this one from this site http://www.vfaq.com/mods/ICtester.html ...checked every coupler for hissing and put soapy water and none are leaking...while doing that i noticed the boost gauge was only going up to 9psi due to the BOV opening up and letting all the pressurerized air out not letting me go past 9psi...

i reconnect everything and do some runs and the car runs at 5psi...i decide to diconnect the actuator and plug up the j-pipe to see if the boost will rise...and it did to 8psi....with the actuator disconnected i should have unlimited boost....im suppose to have a 10psi spring on the BOV so when it reaches that i hear the BOV letting all the air out and back into the system...ive tried 3 different actuators already and they all make me boost at 5psi connected...so i dont think the actuator is the problem...

i also did another test...i connected the boost gauge line to the j-pipe to see how much boost i was generating straight off the turbo and it was the strongest run ive had...actually fealt right...pulled hard...BUT...boost gauge was reading 10 psi right off the turbo...now that makes no sence...NO actuator connected and its reading boost before the BOV realeases the air and only 10psi...idk if im making sense...but i dont think 10psi is correct...i think i might have a bad turbo on my hands but not sure yet...yes the boost gauge is reading correctly and there are no leaks in it...i did a pressure test on the line and it reads fine up to 30+psi with no leaks...

what it comes down to is...why is it that with the actuator connected it boosts only 5psi and with it disconnected only 8 psi...and when boost gause is connected right off the turbo...only 10 psi is detected and no more....

i really wanna fix this...car idles smooth and drives like stock...i dont mind boosting 5 psi for the mean time as i dont race, and i need a car to get me to work and school until the semester is over and i can start working on it again.

any ideas... you can see my set-up and build tread here https://www.thegalantcenter.org/show...=20588&page=19

[4g63lover]

you sure its not a faulty gauge. Cuz if you tapped it onto a line straight off the turbo and you're only reading 10 psi but the car still pulled and ran great Im pretty sure somethings up with the gauge itself... dont take my word for it though. Try using a different gauge.

if not, if the turbo is internally gated make sure the wastegate flap is closing.

[whokilledhoughes]

you sure its not a faulty gauge. Cuz if you tapped it onto a line straight off the turbo and you're only reading 10 psi but the car still pulled and ran great Im pretty sure somethings up with the gauge itself... dont take my word for it though. Try using a different gauge.

if not, if the turbo is internally gated make sure the wastegate flap is closing.

yes i pressure checked the line of the boost gauge and read up to 30psi on the check...and the flap its perfectly closed on the turbo..

[DryBear]

I have a similar problem, where I'm not getting any boost. When I took it to the dyno, the techs were trying to figure it out. I was getting to 3PSI, then I would loose all boost, getting to around 0-1PSI. One of the techs pinched off the vac line to my wastegate and we were able to get boost right away (went to about 6psi). So they determined it was most likely my wastegate causing problems.

I since cleaned out my wastegate, and was able to get to 4PSI, but its back to the same problem of loss of boost. I'm going to order a replacement wastegate and hopefully that will fix the issue.

[whokilledhoughes]

I have a similar problem, where I'm not getting any boost. When I took it to the dyno, the techs were trying to figure it out. I was getting to 3PSI, then I would loose all boost, getting to around 0-1PSI. One of the techs pinched off the vac line to my wastegate and we were able to get boost right away (went to about 6psi). So they determined it was most likely my wastegate causing problems.

I since cleaned out my wastegate, and was able to get to 4PSI, but its back to the same problem of loss of boost. I'm going to order a replacement wastegate and hopefully that will fix the issue.

well ive tried 3 different wastgates...one of them being a forged one...and no luck...bah...this is getting annoying... and remember...im only showing 10psi straight off the turbo with no actuator installed....which has me puzzled

[Stewi]

Okay where do I start....

First off, the BOV spring pressure doesnt correlate to how much boost, but rather how much vacuum. The BOV spring resists the vacuum pressure to the BOV closed under vacuum. The reason you run a hose to the BOV is so that when you let off the gas pedal, the pressure in the hose drops faster than the pressure in the intercooler pipe, which allows the BOV to open and release the back pressure in the intercooler pipe.

Intercooler design & efficiency also plays a big role. Do some homework online about intercooler pressure drop. I have a pretty good intercooler and I run 22psi and I drop to about 20.5 psi after the intercooler.

Also for vacuum leaks, hook up the pressure tester right to the TB and check for leaks in the intake manifold.

Also like drybear said, your wastegate could be malfunctioning casing it to be soo low.

Also, when your checking pressure are you just revving the car in neutral, or are you driving in gear?

How much load the motor is placed under also dictates the boost, I can be in neutral and rev my car to 7500RPMs and I only build about 3psi. Even in first gear the car isnt under enough load to break 14psi.

[Stewi]

OHh and you could also have a sick exhaust leak between the manifold and head or between the turbo and manifold, or a crack in the manifold or downpipe which could cause exhaust gas to escape and not spool the turbo.

[whokilledhoughes]

Okay where do I start....

First off, the BOV spring pressure doesnt correlate to how much boost, but rather how much vacuum. The BOV spring resists the vacuum pressure to the BOV closed under vacuum. The reason you run a hose to the BOV is so that when you let off the gas pedal, the pressure in the hose drops faster than the pressure in the intercooler pipe, which allows the BOV to open and release the back pressure in the intercooler pipe.

Intercooler design & efficiency also plays a big role. Do some homework online about intercooler pressure drop. I have a pretty good intercooler and I run 22psi and I drop to about 20.5 psi after the intercooler.

Also for vacuum leaks, hook up the pressure tester right to the TB and check for leaks in the intake manifold.

Also like drybear said, your wastegate could be malfunctioning casing it to be soo low.

Also, when your checking pressure are you just revving the car in neutral, or are you driving in gear?

How much load the motor is placed under also dictates the boost, I can be in neutral and rev my car to 7500RPMs and I only build about 3psi. Even in first gear the car isnt under enough load to break 14psi.

while doing the boost leak test there are no leak among the intercooler piping and the BOV releases no air until the system reaches 9psi then it starts dumping the excess air out.

as for the actuator i dont think thats it since ive tried 3 different ones...

as for checking pressure i connected the boost gauge right off the turbo and left the actuator unplugged which should have unlimited boost as the actuator will never be activated but only run 10 psi.

im begging to think maybe the spacers are causing the problem...but everything looks sealed along there...might get them welded together in the future to see what happens...

[whokilledhoughes]

OHh and you could also have a sick exhaust leak between the manifold and head or between the turbo and manifold, or a crack in the manifold or downpipe which could cause exhaust gas to escape and not spool the turbo.

i still have a flexible downpipe with clamps...which im sure its leaking nasty...will that effect my spool that much??? havent had money to take it to make a custom DP

[mko]

well ive tried 3 different wastgates...one of them being a forged one...and no luck...bah...this is getting annoying... and remember...im only showing 10psi straight off the turbo with no actuator installed....which has me puzzled

I had similar problem with my 16g when i first got it. The actual flapper wasnt covering the wastegate hole, the shaft somehow got pulled out which resulted in the flapper not covering the hole completly. But as Stewi said check the manifold for cracks and all gaskets, especially the manifold to turbo gasket. Check for kinks on the line that goes to th interior to the boost gauge

[Johnathansgalant]

under heavy load 5psi is max with wastegate and like 9psi without vac line to wastegate.. i went wot on it and it does not feel righ.. He has a flex pipe from the downpipe to the rest of the exhaust and its 3 inch i believe.. I hope he doesnt mind me giving his details ha.. There is an exhaust leak seems very small but dunno bout tb leaks.

[whokilledhoughes]

I had similar problem with my 16g when i first got it. The actual flapper wasnt covering the wastegate hole, the shaft somehow got pulled out which resulted in the flapper not covering the hole completly. But as Stewi said check the manifold for cracks and all gaskets, especially the manifold to turbo gasket. Check for kinks on the line that goes to th interior to the boost gauge

all gaskets were put new before the turbo install...manifold to turbo and manifold to head...those spacers might be doing something but not sure yet...cant see or hear any leaks from there...and now that i think about it i dont think my DP leaking has nothing to do with spool up as its after the turbo and has nothing to do with it spooling..its just exiting faster...ill check up on all the gaskets and the spacers...the problem hopefully is there...

[whokilledhoughes]

under heavy load 5psi is max with wastegate and like 9psi without vac line to wastegate.. i went wot on it and it does not feel righ.. He has a flex pipe from the downpipe to the rest of the exhaust and its 3 inch i believe.. I hope he doesnt mind me giving his details ha.. There is an exhaust leak seems very small but dunno bout tb leaks.

its all good man...im getting there...like u have stated before...it might be in those spacers...idk anymore...gonna get them welded together and see what happens..

[Stewi]

while doing the boost leak test there are no leak among the intercooler piping and the BOV releases no air until the system reaches 9psi then it starts dumping the excess air out.

as for the actuator i dont think thats it since ive tried 3 different ones...

as for checking pressure i connected the boost gauge right off the turbo and left the actuator unplugged which should have unlimited boost as the actuator will never be activated but only run 10 psi.

im begging to think maybe the spacers are causing the problem...but everything looks sealed along there...might get them welded together in the future to see what happens...

when you did the test with the actuator unplugged, and you say you got to 10psi, was it while the cart was stopped and you were just revving, was it while driving? what gear were you in? Boost also depends on load. I could remove my wastegate and just block it off, go for a ride at WOT in first gear and build 13psi, in 2nd build 22psi and in 3rd build 35psi. It all varies depending on load.

Did you ever take the o2 housing off and check the flapper? If not, do that.

Also with the spacers, im guessing you have a gasket between each one, remove them, go to autozone and get copper spray. First clean each gasket with wax/grease remover or alcohol, once dry hang them on a piece of wire or an old coat hanger, and spray them with copper spray, do 2-3 light coats on each side for good coverage. wait about 5 minutes after the last coat and then put it all back together. The copper will fill any imperfections and could possibly seal up the leak that you cant find.

[whokilledhoughes]

when you did the test with the actuator unplugged, and you say you got to 10psi, was it while the cart was stopped and you were just revving, was it while driving? what gear were you in? Boost also depends on load. I could remove my wastegate and just block it off, go for a ride at WOT in first gear and build 13psi, in 2nd build 22psi and in 3rd build 35psi. It all varies depending on load.

Did you ever take the o2 housing off and check the flapper? If not, do that.

Also with the spacers, im guessing you have a gasket between each one, remove them, go to autozone and get copper spray. First clean each gasket with wax/grease remover or alcohol, once dry hang them on a piece of wire or an old coat hanger, and spray them with copper spray, do 2-3 light coats on each side for good coverage. wait about 5 minutes after the last coat and then put it all back together. The copper will fill any imperfections and could possibly seal up the leak that you cant find.

i tested the actuator while driving.. i got to third gear ~45mph and gunned it...tranny dropped down to sencond hit 10psi...switched to 3rd got ~90mhp...still steady 10psi....

before i go out and spend about 3-4 hours trying to uninstall this im gonna wait till i get a proper DP make sure all gaskets and bolts from the DP to the muffler are in good shape and not leaking...then im gonna put some sea foam through the vac. line...that should start forming white smoke through the exhaust system...i would also be able to see while i rev if any smoke is coming off from the spacers or the turbo itself....after that...ill see what i do...

when i got the manifold it came with a new O2 side housing and i got to admit i did see the flapper and did play with it to see how it oppened and closed put did not see if it was sealing properly...

[qnz]

the pressure drop in the intercooler is the reason why youre seeing 8psi at the BOV but 10 at the turbo.

[whokilledhoughes]

the pressure drop in the intercooler is the reason why youre seeing 8psi at the BOV but 10 at the turbo.

i figured that much

[GOOSEY2099]

I have allmost the same setup, I can reach 14 psi at any gear by 2750rpm. This has nothing to do with the gaskets, has to be the IC. is it fleabay?

[mko]

I have allmost the same setup, I can reach 14 psi at any gear by 2750rpm. This has nothing to do with the gaskets, has to be the IC. is it fleabay?

i bet it is what youre sayin, but he cant go over 10psi which means the problems come from the wastegate flapper. It could be stuck open, or it doesnt cover the hole completly

[qnz]

I have allmost the same setup, I can reach 14 psi at any gear by 2750rpm.

wow 14 psi by 2750? I need a smaller turbo.

it could also be a seized turbo that is keeping the boost low? tho a seized turbo shouldnt let you boost anything really. if this is the same turbo I had sold you, i remember it spinning freely tho.