Todd951968

I was going fast up a hill the other day, in boost, and when I tried to come to a stop I had no brake assist. Thankfully, braking was up hill and nobody in front. I pulled over at a friends house and was getting no vacuum to the braking system. Spraying starer fluid under the intake revealed a probably leak at the Air Idle Control Valve. Is this the likely problem? This was the first time the car was out this season, after being in winter storage for about 3-4 months.

Breakaway944

At what point in the icv was it leaking? The intake manifold has two big vac lines coming off of it. The one closest to the front goes to the icv. The one to the rear, depending on year, 1987+ will go to the brake booster and 1986 will go to venturi and eventually to the brake booster and icv. So for no venturi cars check the rear vacuum port. For venturi cars check to see if venturi pulled apart or other hoses failed.

Todd951968

My car is an ‘87. The leak appears to be towards the front of the ICV but I havent taken off the manifold to get a closer look. This is based on spraying starter fluid in the general area front vs. rear.

MAGK944

A lot of icv’s leak especially around the connector, I don’t think that’s your issue. Have you tested the check valve on the booster or listened for any hissing noise when applying the brakes?