[PST Jumala]

Hi. I currently own an automatic 1996 Saab 9000 CDE 2.3 Turbo and Im having a bit of a boost problem. Under acceleration when the car is not fully warmed up boost alternates between 0.5 bar and 1.1 bar, but when the car is warmed up the boost does not rise over 0.5 bar. What is normal boost pressure? Is it overboosting when cold or is it not boosting to full capacity when warm? Also what could cause the boost pressure to go up and down when accelerating?

 

[PST Jumala]

I would certainly check all vac hoses first.
Then, if you haven't checked and cleaned it, check the APC valve, both electrically,ohms reading, and clean it out with carb cleaner,brake cleaner or similar.

They get gummed up.

Then if no improvment check the it gets max boost by disconnecting one of the hoses to the wastegate so it stays shut.

But note: you can get to "fuel cut" easy.
Not a good thing to overdo.

But it will tell you if the turbo is working fine.

So I cleaned the APC valve with some brake cleaner, but had no improvement. Then I disconnected the wastegate hose and it boosted fine. Seems like the valve is faulty. Maybe I'll upgrade to a T7 one. Also when I removed my dash I saw that someone had blocked the vacuum hose coming to the APC/Turbo gauge. I took off the block, but there is no air coming or going in the hose. And whatever the blue connector on the right side of the cluster (when in place) is, it was partially "disconnected" with paper between the pins and the soft bendy "pcb" or whatever. I put it back together without the paper and it works just fine. Where does the APC gauge hose go under the hood?

 

[PST Jumala]

Do you realise that you have modify your ECU, both a small hardware tweak, and a change to.the software map if you change from T5 to a T7 valve?

Yeah I know, I dont have the stuff required to connect my ecu to my pc, so I'll just pay maptun for the valve, connector adapter and the ecu work. I think it was about 150€ from their site.