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boost problem (help)
madteg - 4/9/11 at 09:07 PM

Boost pressure has dropped to 10psi from 18psi. Where would you start to look, turbo,waist gate,intercooler and so on.


Antnicuk - 4/9/11 at 09:24 PM

how do you make 18 psi? is the wastegate spring an 18 psi spring or do you use a boost controller? if its an 18 psi spring, then it may be a boost leak but you normally hear them. It could be a blocked cat if you have one. It could also be a week spring and the door is blowing open but this normally happens overtime not overnight.

If your using a boost controller then check the settings and that it is working properly. If you have a 10 psi w/g spring, then it is likely that the boost controller is not working. Sorry if that is teaching to suck eggs.


Antnicuk - 4/9/11 at 09:26 PM

double post

[Edited on 4-9-11 by Antnicuk]


madteg - 4/9/11 at 09:43 PM

using manual boost controller that has not moved, thinking of getting a new turbo but dont want do shell out cash for no reason.


locoR1 - 5/9/11 at 05:26 AM

Kev if i remember right your running a Mitsubishi turbo? as im running an external tial wastgate I have a brand new Mitsubishi actuator here if you want it. (Probably worth a try)


Antnicuk - 5/9/11 at 08:45 AM

turbos dont normally drop boost when they wear out. They will either start smoking a lot (oil seals) or you will hear the compressor wheel hitting the compressor housing (worn bearings). When that happens you will hear a screeching noise. The turbo might spool a bit later if warn out but its hardly noticeable.

Have you tried adjusting the boost controller to see if boost goes up? is it just a bleed valve or is it one of these spring and ball type?


matt_gsxr - 5/9/11 at 09:13 AM

quote:
Originally posted by locoR1
Kev if i remember right your running a Mitsubishi turbo? as im running an external tial wastgate I have a brand new Mitsubishi actuator here if you want it. (Probably worth a try)


Don't the stock actuators open at fairly low boost?

You could fix the waste-gate closed with a rod, and see what happens (carefully of course).

Matt


atspeed racing - 5/9/11 at 09:40 AM

Start from the begining. Smoke pressure test your system for leaks.

could be something as simple as a split pipe somewhere.

takes a few minutes to do the test.. if that proves not to be the problem.. then you should start looking at turbo controls.. i.e. actuators, wastegates etc.

other worthy checks.. is the air filter or intake pipework collapsing?
any restrictions? intake/exhaust. blocked cat/silencer etc

if all above ok.. then look at the turbo itself.

- colin.

[Edited on 5/9/11 by atspeed racing]


locoR1 - 5/9/11 at 11:31 AM

quote:
Originally posted by matt_gsxr
quote:
Originally posted by locoR1
Kev if i remember right your running a Mitsubishi turbo? as im running an external tial wastgate I have a brand new Mitsubishi actuator here if you want it. (Probably worth a try)


Don't the stock actuators open at fairly low boost?

You could fix the waste-gate closed with a rod, and see what happens (carefully of course).

Matt


A quick Google says about 10psi for the standard actuator.

So looking at the original post of its down to 10psi I would be looking at the bleed valve or pipe work .