Johnny Barbieri

Hi there, I am new to the forum. I am the proud new owner of a cornfield find 1987 924s that I am in the process of resurrecting. In the process of removing the heater control valve, I noticed that the heater outlet elbow pipe located under the #4 intake runner has two nipples on it with rubber fittings on them. One of the fittings is connected to a thin plastic line that runs along under the intake manifold and the other fitting has nothing but a rubber elbow on it and I can not find a loose line that would connect to it. I've had the car running and other than a rough idle it runs like a champ.

1. What are these two nipples on the heater outlet pipe for?
2. Would the rough idle have anything to do with the missing plastic line from one of the fittings on the heater outlet pipe?

V2Rocket

commonly known as the bunny ears, it's part of the EVAP control system.

basically, one "ear" goes to the nipple on the throttle body ahead of the throttle plate.
the other "ear" connects to the vacuum pot/valves located on the driver side inner fender, above the brake booster/clutch master cylinder.


"thermost. valve in coolant circulation" right side of diagram..