Suddenly no boost anymore...
 

Here's what happened to my car (stock '87 TII): Yesterday I Was driving home, stoped and got some gas, carwash and left the station with with it to the floor. Everything worked fine. A couple minuites later on the drive home the oportunity arose again and I gave it some gas. This time there was NO boost! It hasn't worked since.

When I give it gas it reacts close to normally from 0-2700 or so. At that point the boost gauge will go to about -10 x10mm Hg. If I hold it to the floor for the whole range the boost gauge gradually drops down to -20mm by ~4500rpm. There is substantially more power between 2000-3000 rpm than the rest of the range. Beyond 3000 it revs slow the and performance sucks more that I would have expected if it was only the turbo not working. At no point does the turbo spool up.

Sorry for the length, but I'd appreciate any suggestions. Thanks.

You hear any air noise, like a whooshhhhh comming from under the hood? May just have a hose loose or cracked. Check the one from the turbo up to the Airflow Box and also the hose from the turbo up to the intercooler, there is a short (4 or 5 inches) rubber piece. I had a rubber one that blew out so i got a silicon hose to put back on.

No I haven't noticed such a sound? Would I nessisarly while I'm driving or do I need to pop the hood to hear it? I'll check that hose out, thanks.

You should be able to hear it from inside the car. It will sound like ALOT of air rushing out from someplace. WHHOOOOSSHHHHHHHH and will keep whooshing as long as your hard on the gas is it's a cracked or loose hose.

I had a similar problem to this and it turned out to be the fuel pump. It just couldnt supply enough fuel when the engine is trying to boost.

yeah if you had loose hose or serious vacuum leak it would idle like shit also, how is car idling?

It's never idled really well. It's usually ~1100rpm, other times it will be 750rpm. When it's at those levels it's usually pretty stable, but it will a fluctuate a bit, about +/-100rpm. However, this behaviour is identical to the way it was before.

One thing I'd like to mention, it's been very cold lately. I don't think the engine has ever been outside when it's been like this. Any chance a gasket went or something? (vacume hoses also being rubber might be susceptible?)