[murphwiz]

I posted a while ago about my apparent lack off boost, car is 9-5 2.3 lpt running at stage 2.

currently getting 0.6 bar at WOT, this i'm told from many sources is low!
the software I'm running should give around 0.9bar.

So far I've:
Cleaned and lube'd the forge piston type BPV
Checked hoses, no apparent leaks as vacuum readings are ok
Checked actuator works, holds pressue etc.
Adjusted actuator rod, shortened 2 turns, with no change!

What next?
I'm thing boost control solenoid, they are cheap for T7 so I've ordered a new one... any futher ideas?

 

[murphwiz]

Replaced BPC valve, still no joy

 

[California Saab Tuner]

Faulty pressure signal perhaps?

 

[sgould]

Are you reading this off the boost gauge in the cabin? Has it been checked or calibrated?

When you say the boost is low, is it not making that at all or is the waste gate opening too soon (or leaking?).

Alternatively are you measuring at the same point as the tuner? IIRC you have tapped the gauge off the inlet manifold. Is the tuner quoting a pressure at the turbo? This would be the higher pressure and make him look good. The pressure drop in the system could, perhaps, make the difference you have found.

 

[cbullock]

Any luck yet Leon?

 

[murphwiz]

Not yet...
Tried a digi test boost gauge thingy, that he managed to borrow just to confirm what I thought was going on

Slowly eliminating possibles, tech2 shows no faults

glad I don't pay for garage labour!

 

[billj]

Tried replacing the Forge with a known good Bosch unit just to eliminate it completely? Had the same problem with a Bailey valve on my 9000 Aero.

Possibly a weak actuator blowing open under exhaust gas pressure?

 

[murphwiz]

I will try a different BPV, also going to replace vac lines with silicone just in case..

Think I've ruled out anything turbo related, I removed the actuator vac line, and boost was there up to fuel cut

 

[billj]

Does the boost gauge go well to the left on overrun? As far as it used to? That was what alerted me to the leak that turned out to be the valve - the boost gauge wasn't going very far to the left on overrun. A boost leak is probably also a vacuum leak.

 

[billj]

Oops - you said vacuum levels are OK