Boost issues R33 GTST
Discussion
I have a modified R33 GTST running a garrett/nissan hydrid turbo its been running fine at 18psi/1.2 bar for over 2 years but has started to play up
Recently it was boosting wildly , peaks were over 30psi briefly and i was getting no control of the boost , so i disconnected my boost controller (Greddy profec b ) and connected the actuator up directly
The actuator pressure is 7psi but i was getting boost creep as the rpm was rising it was going from 7 psi to about 14 psi this is normally a symptom of a wastegate restriction but as i said the car has been fine for 2 years +
I figured the actuator could be playing up so ordered a new HKS branded (Garrett made) item.
Fitted that today again connected directly to a pressure source and its no longer creeping .....hooray!!! BUT one minute it will be solid at 14psi (the HKS actuator has a stronger spring) and then after a gear shift it will be stable at 10psi , come off the throttle and then back on and its pops up to 14psi
Any ideas ???
I'm pulling my hair out here
Recently it was boosting wildly , peaks were over 30psi briefly and i was getting no control of the boost , so i disconnected my boost controller (Greddy profec b ) and connected the actuator up directly
The actuator pressure is 7psi but i was getting boost creep as the rpm was rising it was going from 7 psi to about 14 psi this is normally a symptom of a wastegate restriction but as i said the car has been fine for 2 years +
I figured the actuator could be playing up so ordered a new HKS branded (Garrett made) item.
Fitted that today again connected directly to a pressure source and its no longer creeping .....hooray!!! BUT one minute it will be solid at 14psi (the HKS actuator has a stronger spring) and then after a gear shift it will be stable at 10psi , come off the throttle and then back on and its pops up to 14psi
Any ideas ???
I'm pulling my hair out here
The boost control pipe is currently only about 4" long from the turbo pressure side direct to the actuator
Think i'm going to have to take off the turbo elbow and have a look , i did wonder if the wastegate was being fouled as the current fault is almost the complete opposite of what the original fault was
Think i'm going to have to take off the turbo elbow and have a look , i did wonder if the wastegate was being fouled as the current fault is almost the complete opposite of what the original fault was
yep it is internally gated it moves fine with the actuator off when you move it by hand but there could be a foreign body in there somewhere
OR
I do have one of those turbo elbows where the divider between the gate and the outlet is bolted in place , its been loctited in place with special high temp stuff but it could be moving i guess
OR
I do have one of those turbo elbows where the divider between the gate and the outlet is bolted in place , its been loctited in place with special high temp stuff but it could be moving i guess
liner33 said:
yep it is internally gated it moves fine with the actuator off when you move it by hand but there could be a foreign body in there somewhere
OR
I do have one of those turbo elbows where the divider between the gate and the outlet is bolted in place , its been loctited in place with special high temp stuff but it could be moving i guess
One of them divorsed pipes for a screamer?OR
I do have one of those turbo elbows where the divider between the gate and the outlet is bolted in place , its been loctited in place with special high temp stuff but it could be moving i guess
no the pipe is divorced but comes back into the elbow
like this one
http://www.driftworks.com/catalog/popup_image.php?...
like this one
http://www.driftworks.com/catalog/popup_image.php?...
liner33 said:
no the pipe is divorced but comes back into the elbow
like this one
http://www.driftworks.com/catalog/popup_image.php?...
Oh right. Whats the point of that?like this one
http://www.driftworks.com/catalog/popup_image.php?...
liner33 said:
That would make sense but to be fair its been on the car 3 years and has worked ok up till now
Someone else has mentioned that SX's have an issue with the bushing that the wastegate arm sits in coming adrift i wonder if this could be the problem
Does sound like a wastegate prob if the actuator was replaced. Get that turbo off, and a GT30r on there Someone else has mentioned that SX's have an issue with the bushing that the wastegate arm sits in coming adrift i wonder if this could be the problem

Update
Took off the actuator AGAIN and backed off the tension meaning that the actuator would let the boost off at a lower level , checked the movement on the arm of the wastegate prior to removing the turbo and it moves really nicely couldnt get it to hook up at all and there is no play whatsoever so decided to spray it with WD40 more to flush out any contaminants rather than to lube it as i know it would only last minutes anyhow decided there was no point in removing the tubby
Road test gave stable boost at 7 psi , decided to switch on the boost controller , low boost gave 14-15 psi as before but high boost was a bit low , decided to wind this up but still couldnt get it high enough , highest i managed was 17.4psi but the boost dropped back to 15 as the revs rose , whether this is a return to the other problem or whether this is a function of the boost controller i dont know
In the process of checking everything for leaks i managed to snap the pressure feed for the BOV so road test was cut a bit short, so car is in bit while i repair the BOV
I'm hoping the boost backing off now is down to the limiter function of the profec b but the instructions are worse than useless and i dont really understand them the limiter was set to 20 on a scale of 0-20 so i've set it to 10 and will give it another road test
Took off the actuator AGAIN and backed off the tension meaning that the actuator would let the boost off at a lower level , checked the movement on the arm of the wastegate prior to removing the turbo and it moves really nicely couldnt get it to hook up at all and there is no play whatsoever so decided to spray it with WD40 more to flush out any contaminants rather than to lube it as i know it would only last minutes anyhow decided there was no point in removing the tubby
Road test gave stable boost at 7 psi , decided to switch on the boost controller , low boost gave 14-15 psi as before but high boost was a bit low , decided to wind this up but still couldnt get it high enough , highest i managed was 17.4psi but the boost dropped back to 15 as the revs rose , whether this is a return to the other problem or whether this is a function of the boost controller i dont know
In the process of checking everything for leaks i managed to snap the pressure feed for the BOV so road test was cut a bit short, so car is in bit while i repair the BOV

I'm hoping the boost backing off now is down to the limiter function of the profec b but the instructions are worse than useless and i dont really understand them the limiter was set to 20 on a scale of 0-20 so i've set it to 10 and will give it another road test
liner33 said:
Update
Took off the actuator AGAIN and backed off the tension meaning that the actuator would let the boost off at a lower level , checked the movement on the arm of the wastegate prior to removing the turbo and it moves really nicely couldnt get it to hook up at all and there is no play whatsoever so decided to spray it with WD40 more to flush out any contaminants rather than to lube it as i know it would only last minutes anyhow decided there was no point in removing the tubby
Road test gave stable boost at 7 psi , decided to switch on the boost controller , low boost gave 14-15 psi as before but high boost was a bit low , decided to wind this up but still couldnt get it high enough , highest i managed was 17.4psi but the boost dropped back to 15 as the revs rose , whether this is a return to the other problem or whether this is a function of the boost controller i dont know
In the process of checking everything for leaks i managed to snap the pressure feed for the BOV so road test was cut a bit short, so car is in bit while i repair the BOV
I'm hoping the boost backing off now is down to the limiter function of the profec b but the instructions are worse than useless and i dont really understand them the limiter was set to 20 on a scale of 0-20 so i've set it to 10 and will give it another road test
Turn the limiter off on the profec. Adjust the gain to get it to hold the boost .Took off the actuator AGAIN and backed off the tension meaning that the actuator would let the boost off at a lower level , checked the movement on the arm of the wastegate prior to removing the turbo and it moves really nicely couldnt get it to hook up at all and there is no play whatsoever so decided to spray it with WD40 more to flush out any contaminants rather than to lube it as i know it would only last minutes anyhow decided there was no point in removing the tubby
Road test gave stable boost at 7 psi , decided to switch on the boost controller , low boost gave 14-15 psi as before but high boost was a bit low , decided to wind this up but still couldnt get it high enough , highest i managed was 17.4psi but the boost dropped back to 15 as the revs rose , whether this is a return to the other problem or whether this is a function of the boost controller i dont know
In the process of checking everything for leaks i managed to snap the pressure feed for the BOV so road test was cut a bit short, so car is in bit while i repair the BOV

I'm hoping the boost backing off now is down to the limiter function of the profec b but the instructions are worse than useless and i dont really understand them the limiter was set to 20 on a scale of 0-20 so i've set it to 10 and will give it another road test
liner33 said:
I dont know whats "off" on the boost limiter is it 0 or is it 20??
0 is off.Heres the manual:
http://www.alamomotorsports.com/greddy/PROFEC_B_SP...
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