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Rb26 Not Boosting Properely

SUN32RISE

By SUN32RISE,
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SUN32RISE Contributor

SUN32RISE

Posted
Posted (edited)

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 by SUN32RISE
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Thor250f Rookie

Thor250f

Posted
Posted

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 Grand Master

Moodles2

Posted
Posted

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 Grand Master

MrStabby

Posted
Posted
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.

  • 2 years later...

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