SAAB 93 Turbo Diesel (Vauxhall Engine) Year 2002Archived Message
Posted by Dave Hill on June 26, 2007, 9:34 pm
I have a 2002 Saab 93 Turbo Diesel, same as seen in the Vectra/Zafira. It has had a new turbo fitted at a local garage but now it has no boost. There are no fault codes present.
It has a variable vane turbo & the actuator can be seen to "suck up" as soon as the engine starts. In this position it will not rev above 3,000 rpm. The garage has replaced the vacuum control valve that controls the diaphragm.
I haven’t studied the way these valves worked before & I assumed that they were just an open/closed device. After checking it with a switched feed & earth, it appears that "the vac" in "vac out" connections are not blocked & un blocked, but instead it merely opens up to atmospheric pressure, thus allowing the vacuum to escape (through the third vac connection open to atmosphere).
Anyway I digress! It has two of these valves fitted & both seem to work ok. The guy seems pretty confident that he hasn’t altered the way the vac hoses are connected. I have studied the way the valves are connected on a similar Zafira & they look to be the same.
I thought I had found something when I found a disconnected lever on the inlet manifold that is also controlled by a vacuum solenoid.
If I manually operate the Turbo diaphragm with the mitty vac whilst the engine is revving I can feel the intercooler hoses swell as the pressure increases.
Has anyone got any details about the correct routing of the vacuum hoses, or any other info that could point me in the right direction?