Ok my car died tonight and wouldn't restart. It's an 87 TII and was just running terrific. I was driving down the highway, slowed for a toll booth and the motor just died. I was still going about 40 so I just popped the clutch and restarted it. It ran for a little bit but would only run if I gave it a little gas, but if I gave it over 10% it would die. I pulled over to see what was wrong and it died and wouldn't restart. When I turned the key it would start, rev to 1000 rpm and immediately die.

The first thing I noticed when I looked down at my SAFC was that the Air Flow % was at 0. Strange, I thought maybe my AFM came unplugged or went bad. So I took off the filter and pushed it with my finger, the SAFC read it just as it was supposed to. Ok I thought it must be a "massive" vaccuum leak like a hose popped off the intercooler. Well all hoses checked out.

Here's the strange part. Normally my factory boost gauge sits all the way to the bottom (in the -mm/hg part) unless you are in boost, and then it behaves normally. Now as soon as you turn the key it jumps to the "0" mark at the lower middle part of the guage.

This is not the first time it has happened to my car, but this is the
first time it has happened since I put in the new motor. It only
happens when the gas tank is below 1/3 a tank.

 

Hmm..

If it only happens with 1/3 tank, could be air in the lines. Have you dropped the tank and checked the pump, strainer (2nd fuel filter), etc..