Hello everyone,
I have a 1986 saab 9000 turbo, and I am having some dificulties with my APC gauge. To my knowledge, the gauge is supposed to go up when you press on the accelerator, showing the amount of boost? well my gauge never sways from its 1/3 position. Any information on how to fix/what the problem is or what I need to replace would be greatly appreciated.

-Matt

The small bore vacuum hose that connects the APC gauge to the engine intake manifold gets hard with age and splits or falls of the connections.
Check along its length under the bonnet from the dump valve toward the bulkhead, you'll probably find a split somewhere along the way.

Nick.