[1QUICK2.0T]

tooling around with my car on the way back from work nothing unusual just putting the pedal to the floor sometimes when one of the times i decided to step on it from 2nd i watched the boost gauge clime to 12psi and stop while still at 4500rpm in 2nd i put it in 3rd usually spikes a little over my regular 15psi that i run with MBC, and it still only made 12 psi, pull over crank the MBC all the way up still only hitting 13-14psi.....no visual vacum leaks boost gauge acting fine beside the car isnt hitting boost its soposed to !!!! , i cant even get fuel cut if i want, usually i set it right perfectly at 15-16psi so it wont hit fuel cut at 16+ psi, now like i said i cant even get there if i want,
i got a 87' 9000T,
thanks

 

[MartinR]

I'll move your post to the 9000 forum.

 

[billj]

Does your boost gauge go as far down as it used to go on overrun? If not, suspect a leak somewhere. Last time this happened to me, it was a leaking dump valve. Worth checking this if you've checked all the hoses, etc.

And if you replace it, don't forget to close off the bleed valve before you start testing

 

[1QUICK2.0T]

to answer your question no it dosent go as far as it used to, i bought the car few months ago and it alredy had a blastic Bosh BPV.....???? do those leak ever?, sorry but whats the bleed valve are you talking about the stock Boost controller with 3 holes?

 

[billj]

Sorry, "bleed valve" = "MBC". Just sayingf not to forget to turn it back down when you fix the problem.

Yes, the Bosch valve, like any other, can and does fail. The lack of vacuum showing on the boost gauge indicates a leak and the valve is a distinct possibility.

 

[1QUICK2.0T]

thanks a bunch Bill, i gotcha now , well i guess i'll try to get one from the dealer here, one question though is that stock on the 87s ? cuz i heard people saying that the blastic bosh unit is like an upgrade for my year car, now if its not when i do call Saab dealer which car should i say i have cuz that will be the esiest way to get it if i say i got a 96 9000 t , and if i try to explain it will make it a lot harder, the only thing is though on my boost gauge it used to idle at -10 vacum now its like -8, but the gauge its kinda hard to read, like i said its plobably a very small leak cuz i'm only loosing like 3 psi at my regular setting.