[swifterpete]

Hi, I've just been to look at a car for my girlfriend, 9-3FPT 1998. it is in great condition and only 67k on the clock. The only problem with it is that the turbo is only boosting to halfway on the gauge. It drives as smooth as silk but I know from my old 9000FPT that it should give a bit more boost than that, just under the red as far as i can tell. There was no real turbo push from this one which I know isn't right.
The seller didn't think it had a problem but may have been driving it like that for ages and not really realised it should boost more. He said he didn't like to push it too much.
When I had overboost probs in my 9000, a clean of the BPC sorted it out, is there any chance it's that playing up now? If it is that then I know they're pretty easy to replace so it isn't a problem.
If it's cheapish and easyish to diagnose then I'm still interested in the car, any ideas on what to look for to tell what is causing it/fix it?
I'm halfway reticent at buying a car that has problems before it's even mine but it is very clean and in good nick other than this boost problem.

cheers in advance.

 

[PMI]

Half-way into the yellow is base boost, which is what you get if the BPC valve is bypassed, unplugged, wire broken, bad, or if boost control is not working for some other reason.

The BPC in the 900 turbo is subject to the same clogging and other issues as the 9000, but I don't think I would let that deter me.

Similar thing can happen with a boost leak, like a cracked hose between the intercooler and the engine, or a loose hose clamp. However, when one of my clamps let go, the engine did not run "smooth as silk" by any stretch, :cheesy:

 

[earthworm]

Welcome to SaabCemntral, SwiftPete

The 900 and 9000 are very similar in many areas and if the 900ng boost control is cleanable - all the better.
Or you can buy and install a "MBC"...

 

[swifterpete]

Thanks for the welcome.The car isn't going to be mine so I don't really want to start messing with mbc's and adjusting boost levels. I just want it to drive like it should as it's going to be my girlfriends car with me just nipping out in it sometimes!

So the BPC is likely then you think PMI? If loose clips and hoses cause rough running, I don't think it's that as it runs and idles very well.
I've heard that the wastegate sticking can also cause problems, is this an easy repair if that's the issue?

 

[PMI]

If loose clips and hoses cause rough running, I don't think it's that as it runs and idles very well.

I think it depends on the size of the leak. In my case, it was noticeable any time I stepped on the gas.

If it accelerates normally, but the boost pressure does not build past mid-yellow, then it is something to do with boost pressure control.

I don't see how the wastegate could cause this. If it sticks closed, then you get overboost and fuel cut. If open, you get little little or no boost, not even base boost. If it was mis-adjusted, or actuator rod loose, maybe...

 

[swifterpete]

Well that's reassuring then. I have looked on the net and new wastegate actuators look to be about 100 quid, BPC's on ebay are only a few quid and hoses aren't too much either..
Hmm, got to wonder whether it's worth taking a risk and going for it. My girlfriend is worried about buying a car we already know has a problem, I'm trying to convince her (and myself!) that it could be something easily fixable.
cheers for the help so far.