Rb26 Not Boosting Properely

[SUN32RISE]

hi guys driving to work today my rb26tt was not boosting above 3-4 psi, from memory it would go up to around 7. it's not blowing any smoke at all or are there any other signs of blown turbo.

when spooling they sound clean but can't really tell if it's the one or two of them,

what is the standard boost for a rb26 as mine is completely stock?

with only 4 psi it lacks a bit of power thats what got me wondering.

any help or knowledge would be greatly appreciated

Edited July 31, 2009 by SUN32RISE

[Thor250f]

Hey mate, not going to help, I've just started having the same trouble with my Gtr. Won't boost past .5 bar? Just started happening and I thought it would be a vacuum leak somewhere? After FMIC? My idle also drops sometimes so thought this may all be linked?

Two people with the same issue. Lets see how we go

[Moodles2]

10-11 psi is standard boost on a R32 GTR, 14.7 psi if the restrictor has been taken out.

On the factory boost gauge, +7 mmHg equals 13.5psi

[Thor250f]

Yes, but why are they just flat out stopping at .5 bar???

[Moodles2]

Check the front of your catalytic converter (drop it between the front pipe and cat), if there's no ceramic wheel or bits of turbo exhaust wheel, assume the turbos are still ok.

Next I would look for is a boost leak, go over the intercooler piping with a fine tooth comb, undo it all and put it back together, replacing dodgy clamps.

If it's a throttle body gasket or intake manifold gasket (it's not uncommon since theyre paper based, and easily blown with age), spray aerostart or brake cleaner around the t.b. and i.m. gaskets.. if there is a leak the engine revs will react to the spray.

Probably other things it could be, like the exhaust manifold gasket, snapped exhaust stud or snapped stud holding one of the turbos.. these 3 things could be venting the boost in the enginebay, although they usually make some sort of sound like whistling etc.

[MrStabby]

Check the front of your catalytic converter (drop it between the front pipe and cat), if there's no ceramic wheel or bits of turbo exhaust wheel, assume the turbos are still ok.

It cant be a broken turbo - you dont make any boost when that happens BTDT.

[CAY570]

Having this problem myself. not boosting over 0.5 bar. You guys found what was the causes?

[MrStabby]

Could be collapsed cat or intake leak.