Only getting 5lbs of boost

My Friends 89 TT is only making around 5lbs of Boost
have checked error codes with Conzult and all good (code 55)
have performed a boost leak check and alls good
anyone have any idea what could be causing this

 

What type of guage are you monitoring the boost with?

Stock turbo setup or has it been modified in any way?

 

Is the car stock? is there are boost controller? and to the others with more knowledge can a car be in safety boost but not give a code (eg if the car actually is opinging will the knock sensor throw it into safety)

 

Yes and yes. But the safety boost condition should clear if you restart the engine.

 

it would but if someone has played with the timing (you know the old "lets advance the timing till it pings so we can get more powar!!") they could be setting the knock detector off.

I would be inclined to get a timning check as well as looking for boost leaks and also the possibilty of a turbo/wastegate issue

Vague answer I know but we dont have much in detail to diagnose

 

Take the car for a actual drive when you have consult plugged in.. take note of when the "wastegate open" check changes ...

If its all clear on codes, no boost leaks... then im assuming that your wastegates are opening way to soon.

 

Safety boost is 7psi not 5. 5psi is wastegate pressure which leads me to the question:
Are the factory solenoids bypassed from the waste gates straight to the intake without an aftermarket boost controller?
Was it always making 5psi or did it just suddenly happen one day?

 

you just pop up everywhere dont you.. haha ""

BUT
what he said. / asked ?

 

Gate pressure is 7psi. This is also safety boost. Normal operating pressure is 9psi.

Verify the gauge accuracy before you get too carried away.

 

Also, bear in mind if the circuit that contains your detonation sensor and/or coolant temperature sensor is out of spec, then you can restart your engine as often as you like and you will = safety boost and maps instantly.

As someone already said, get someone with a laptop and conzult to check it out.

 

Oops. Well either my gauge is out or my wastegate springs are lazy.

 

I am only suggesting that it could be safety boost as 5 psi is close to 7 and a cheap guage can easily read 2 psi out, not saying he has a cheap guage but as has been mentioned already we dont know what he has. also my guage is accurate but the dial/face can actually be turned (if you are keen) I turned mine while installing it (hole was just a tad to small) and only noticed as I went to start and I was sitting at 2psi with the engine off.

 

if he was in safety im sure he would have the other "precuationairy" measures .. rich fuel tune, timing etc .

Im goin to put my 5c on the actuators

 

car was running 12lbs boost and then just dropped down to 5
have tried another boost controller and no difference
and is way down on power it is running am aftermarket boost guage as well as original one and both read the same pressure and have checked with conzult and no error messages

 

boost leak

 

Aftermarket BOV's as well as OEM Recirc valves at the same time?

Seen it before, but not sure what it was boosting to

 

if one of the turbos is rooted ( ie: jammed still) or the compressor wheel is hammered after having something stuck in it. So only one turbo is boosting.

AND the car is set to normal/stock boost level ( 9psi) with NO codes. The resulting boost level is about 5PSI

MAybe thats your issue.

 

+1 to this as a possibilty
I had a waste gate jammed open as such one turbo was not spooli8ng the best I could get was 7 lbs had a hell of a time trying to sort this issue

 

have done a boost leak check all ok
am thinking a jammed wastegate or a stuffed turbo
it has after market BOV's but recirc valves have been removed