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need help i have a r33 gtst and for some reason its been over boosting to around 14/15 psi and cant find out why i have replaced all my vacuum lines replaced my actuator and checked my intercooler piping and clamps. i am currently using a t piece boost controller from turbo smart i took it off thinking it was faulty and put the standard factory one back on. and it is still boosting at 14/15 psi. i put the turbo smart t piece back on wound it right down and then turned it up 2 clicks and is still boosting the same any help from anybody would be appreciated.

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what mods do you have (such as intercooler, etc)?

i ofund that after i put on my fmic i was getting servere boost spiking because the hose to the wastegate was coming from the manifold (new pipe that didn't have the nipple on it like the old one). so i cut the nipple off the old piping and welded it into the pipe from the turbo to the cooler and boost became steady as a rock.

i would go and buy a new length of hose and run it straight from wherever you currently have it hooked to the cooler/intake to the wastegate. don't run it through the boost solenoid or anything like that. then if it still runs high boost then it is either going to be that you have it hooked to the wrong place to start with, or your wastegate flap is fouling on the dump pipe.

wastegate flap is fouling on the dump pipe.

Im gonna x2 that.

I had the problem too, but i wasnt spiking that high, more like 11-12psi. It ended up being the dump pipe so got it "enhanced".

I set my EL2 Meter to .08bar (12ish-psi??) warning, and on the track, on the back straight at full throttle it blinked once or twice at the top of 3rd and top of 4th. But did drop back pretty quick. Wondering if it is still the wastegate/dump pipe. (JJR Split POS)

Will try an R32 Actuator too.. might help. You could try that too?

  • 4 weeks later...
I had problem with my dump pipe as well. It's JJR (from just jap). And mine spikes to 15ish aswel and then goes R&R

thanks for all your help i have tryed everything that you all said and still no change i think its time to get it on the dyno and see if they can find it cheers

thanks for all your help i have tryed everything that you all said and still no change i think its time to get it on the dyno and see if they can find it cheers

The way you can test whether its the dump pipe is by removing the turbo heat shield, taking the actuator rod off, and seeing if the wastgate opens freely. (push it back and forward to see if its hitting the dump pipe). It'll take you about 5 minutes to test that, if it is hitting something, then its the dump pipe.

I started a thread on it a while back in the forced induction forums...(theres a few pictures there aswel if you're unsure what I'm talking about, or you can pm me, I'm more than happy to try and help you out).

For the record, I couldn't get mine to work, so I'm still chasing down the workshop that sold it to me for an exchange for a bellmouth one. I know of another person that had the exact same problem and was fixed by changing to a bellmouth design dump pipe.

The way you can test whether its the dump pipe is by removing the turbo heat shield, taking the actuator rod off, and seeing if the wastgate opens freely. (push it back and forward to see if its hitting the dump pipe). It'll take you about 5 minutes to test that, if it is hitting something, then its the dump pipe.

I started a thread on it a while back in the forced induction forums...(theres a few pictures there aswel if you're unsure what I'm talking about, or you can pm me, I'm more than happy to try and help you out).

For the record, I couldn't get mine to work, so I'm still chasing down the workshop that sold it to me for an exchange for a bellmouth one. I know of another person that had the exact same problem and was fixed by changing to a bellmouth design dump pipe.

ABSOLUTELY........................... what he said....

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