1jz wont boost past 10psi, possible turbo failure soon?

[77GZE]

Ok, tailshaft is fixed....
have not checked pvc valve....
but couldnt hear it leak at all (hissing) when i boost tested the whole setup...
im driving it now...
10psi again
its really fucked
i have a high quality stainless dumps and exhaust on it...
everything to match
once was hitting boost cut
now not

[77GZE]

anyone? no more ideaS?

[broken22]

wastegate creep, due to lazy worn out actuators.

[abently]

Well its definately a wastegate issue of some sort. Is there any cracks forming around the wastegate port on the Turbine housing ? I.e. such that the wastegate flap can not be sealing the port perfectly ? That would be my main suspision. It doesn't even need to be a minor crack, just a warped surface is enough to cause issues.

I know it will be a pain in the arse to check but if that checks out fine, then pull off your Wastegate diaphram and get it tested.

[77GZE]

I have read in a couple of places about cracked wastegate seats, but in saying that...when i pressureised my system with the boost leak tester....it was fine...im now assuming the actuator springs might be a bit fucked...but nowhere have i heard of this with 1jz's?
ffs!

[richzx]

Does seat of the pants tell you its slower? My car with dumps and
3" exhaust only gets 10psi-10.5psi on the actuators and only ever has, so has my bro's with 2 1/2" dumps into 3" exhaust is the same.

[77GZE]

yeh but unless my old gauge was faulty....i dont know..
when i got the dumps done, and the 3" on it i was hitting boost cut, but now...not so much...
i duno?

[Rosie]

U said u have 3 spare sets - change the actuators over if u have spare ones.

Got a 1G and it hates me at the moment too, minor leaks were killing a fair bit of power / psi.

[82MKII]

Have you been out in it on a cooler morning? Mine makes more boost on the cool mornings. Maybe just the hot weather slowing you down!

[web]

I have read in a couple of places about cracked wastegate seats, but in saying that...when i pressureised my system with the boost leak tester....it was fine..

The boost leak tester pressurizes the intake side only and would not show wastegate leaks since the wastegate is on the turbine side.

[abently]

The boost leak tester pressurizes the intake side only and would not show wastegate leaks since the wastegate is on the turbine side.

Yes, otherwise it would be showing up a major boost leak.

[77GZE]

hahahaha, well guys, its running 14.7 again.....
its wastegate creep...
i found out that the bleed valve i had in it had been assembled wrong when i first got it!!!
the gate was on the wrong side...
have sent turbosmart an email about it..
now the gate it working properly, and no wastegate creep!!!
its much better...
so, without the bleed valve on...
it will only run up to 11psi...
which im told isnt too bad concidering im still running a cat and stock turbo piping and a cooler...

[ra28_miles]

man this was a good thread to read
Who would have knowen a new turbo bleed valve had been assembled wrong???
How do you check that crap???
A cummins K19 (diesel 19lt straight six) came into my work with high blow by
So off came the heads and the pistons looked a bit tired. After rebuild still high blow by!!!
Turns out the recon turbo's sealing ring on the turbine side did not seal from factory!!!
Causing exhaust gas to re enter the crank case via the turbo drain, causing hi blow by!!!
Go figure