[Boru84]

I'm in the process of getting my cheap craigslist SPG running smoothly. After a recent test drive I discovered a vacuum leak. It looks like a line is missing on a plastic fitting on the intake manifold. There's a massive sucking noise from the fitting and blocking it off with a finger makes the engine stall out. I've added pictures below. A buddy and I looked over a vacuum line diagram and couldn't find a missing line. For what it's worth, the plastic fitting looks like it accepts a larger line than the typical 4mm size.

Can anyone with more experience with these engines offer advice?

 

[peva]

Maybe the hose to the cabin ventilation vacuum reservoir in the bulkhead behind the PS reservoir tank. Could be the dark purple hose in this link;
https://photobucket.com/gallery/htt...er/turbocon86/media/c900vacdiag_ricd.jpg.html
The nozzles on the manifold are not designated for particular uses.

 

[jvanabra]

Looks like someone swapped some stuff around, and maybe some stuff missing.

The things that should have vacuum:

1. Bypass valve
2. Fuel pressure regulator
3. Small PCV line (with check valve)
4. Evap valve
5. Evap canister purge
6. Brake booster
7. To cabin (APC sensor, turbo gauge, etc.)
8. To vacuum reservoir

Generally speaking, you want closed systems (like FPR + BPV) ganged together and open systems (like evap purge and PCV) ganged together. Otherwise you can get slow responses to closed systems.

It's been a while since I've looked at LH 2.2 with a vacuum operated evap purge valve, but think that's what's missing. From memory, the front position is #1+#2+#4 (closed sources). The rear position is #3+#5+#8 (open sources) and the side position is #6+#7 (closed sources).

 

[vsfoxe]

On my 1990 SPG, one line goes to the top of the Fuel Pressure Regulator, the other line goes to the Blow Off Valve. Hope that helps (my car runs great). Vern