boost leak or bad wastegate acuator

[mattspyder]

i can get up to about 5psi, ill be almost up to about 5 or 6 rpms, and my car just struggles to get up there, boost wont go any higher, what does this sound like?

 

[Quasimondo]

You have an internal or external wastegate? If it's internal, checo to see if the flapper is still attached to the wastegate arm. If it's external, check to see if it's not stuck open. Either way, it sounds like all of your exhaust flow is bypassing the turbo.

 

[mattspyder]

yes i have a internal, but i think it might not be opening that would cause it to do that right..

oh yes the arm is still attached, to adjust the arm do you make it longer or shorter i cant remember which one it is??

isnt there a way to test to see if its my flapper not opening up?

i have a t04b vtrim

 

[92awddsm]

yes i have a internal, but i think it might not be opening that would cause it to do that right..

oh yes the arm is still attached, to adjust the arm do you make it longer or shorter i cant remember which one it is??

If it wasnt opening, it would cause an overboost situation. If it is stuck open, it would cause low boost like what you are talking about.

 

[tstkl]

if its siezed shut you would be seeing well over 10psi depending on which turbo you have,....

 

[92awddsm]

if its siezed shut you would be seeing well over 10psi depending on which turbo you have,....

To4b v-trim.

Shortening the arm will help keep the wg closed and Lengthening it will cause it to open easily.

 

[oldman]

i can get up to about 5psi, ill be almost up to about 5 or 6 rpms, and my car just struggles to get up there, boost wont go any higher, what does this sound like?

1. Check for any exhaust leak before the o2 housing.

2. Make sure the actuator arm is connected to the wastegate lever. If so, remove the arm and make sure the flapper is completely shut with the arm on.

3. Bypass the mbc and test run. If problem solved, problem is the mbc. If it persists, go to 4.

4. Bypass the actuator and do a all out boost test by leaving the actuator nipple open, feather the throttle and do not let shoot straight up. If problem solved, actuator is opening prematurely. If it persists, go to 5.

5. Boost leak test. If this yields nothing, the only thing left would be the turbo itself.

Good luck.

 

[oldman]

To4b v-trim.

Shortening the arm will help keep the wg closed and Lengthening it will cause it to open easily.

Very good point. Many seem to be having problems with keeping the 38mm flapper shut on the Bullseye housing, some one should run a compressor directly to the actuator and see if it real holds the pressure That the spring is rated to hold.

 

[tstkl]

Very good point. Many seem to be having problems with keeping the 38mm flapper shut on the Bullseye housing, some one should run a compressor directly to the actuator and see if it real holds the pressure That the spring is rated to hold.

just jam two in there and call it a day...

 

[mattspyder]

ok how would i bypass the mbc, just unplug the mbc or what?
or is it just run a hose from the wastegate to the stock boost sensor or whatever that thing is down there.

see heres the thing it did this to me when i had my t-25 on, just only once in awhile. like when i got up in rpms slowly, but if i gunned it it wouldnt muffle on me?? weird huh. think i should just sell my car and buy a evo or wrx

 

[Quasimondo]

ok how would i bypass the mbc, just unplug the mbc or what?
or is it just run a hose from the wastegate to the stock boost sensor or whatever that thing is down there.

see heres the thing it did this to me when i had my t-25 on, just only once in awhile. like when i got up in rpms slowly, but if i gunned it it wouldnt muffle on me?? weird huh. think i should just sell my car and buy a evo or wrx

Run a line from where your mbc is getting boost at directly to the wastegate.

Speaking of which, where exactly are you running your MBC from? The intake? Teeing it off from the BOV line? Outlet nipple on the turbo?

 

[mattspyder]

alright well i went to take my intercooler off to clean it thinking its never been cleaned and i noticed that one of the couplers that connects a pipe to the bottom or the intercooler has a big ass tear in it, im talking mabye a inch and a half, right in the middle of the coupler, so much air could be leaving from this, this has got to be my problem huh??