07-03-02, 10:25 PM
I woke up this morning generally feeling like sh*t. I was hoping to hop into the saab and start feeling better with a little boost under my belt, but what happened, no feel. Today the car really started to drag down. Not to badly, but enought that I could feel the difference that she wasn't her usual self. I have been driving her pretty hard lately. The car has 154000 miles and still has the origonal head and tranny, would any of these be the problem. A slow decrease untill POP! Also, over the past couple days I have noticed a odd noise when I let off the gas on a pretty good acceleration. It's a pittering flittering noise kinda sounding like it's between right in front of me and the intake. Does anyone know what this is and whether it has somethign to do with my power? Thanks to any responses.
mod-man (87 900 turbo 16 3 door)
07-03-02, 10:40 PM
I am not 100% sure of this but it sounds to me like it could be your dump valve that is making the noise on deceleration.
There is info about this if you use the drop down menu and search for dump valve (preesumably) but in the meantime there is a simple test you can do. On the vaccuum pipe that leads to the dump valve if you suck on it and find free flow, the diaphram has perished and so needs replaced.
I hope this helps until a knowledgable one comes along.
08-03-02, 07:52 AM
Check ALL of your turbo hoses right the way from the intake to turbo, then from turbo to intercooler and finally from intercooler to throttle body, make sure there are no holes and that the clips are nice and tight, you may have a boost leak under pressure, difficult to tell where its leaking from until your under boost so it just a case of being methodical and checking all of them!
I'll second that, I lost at least 50% of boost last week, and idle rose to 1100 rpm, just a split vacuum hose replaced in 5 mins, back with full boost now! Found it by pinching every hose I could see until idle dropped again, looked carefully an found it had split where I couldn't see it ( just off Turbo in front of the Block).
How hard is it to find the turbo hoses once the leak has been found. If not OE hoses, than what can be used?
08-03-02, 05:27 PM
DanF try these people, they do silicon turbo and vacuum hoses, they are very long lasting and are very resistant to heat and therefore cracking.
12-03-02, 10:12 AM
Do you run an after market cone filter aka k&n? If so then your gettin pulses from the blades when you lift off, dump valve possibly sticking. Or more likely if you run a diaphram dump valve you've split this so it with coo like a bird and release boost constantly. Does this help?
25-03-02, 01:47 PM
Yes. I have an aftermarket cone filter. Where exactly is the dump valve. I am a rookie with these cars. Thanks.