Hi,

After I got my car back from the bodyshop I was snooping around in the front left fender area, and came across a round plastic hollow ball with a vacuum line attached to it. The ball isn't bolted to anything, just sits on one of the fender supports, and you can move it around easily. I never hear it rattling around. I didn't even know it existed before I snooped around, so I don't know if the bodyshop knocked it off it's support, or if it was always just sitting there. Anyway, what is this thing ? Not the charcoal cannister, right ? And where does the vac hose go ? Maybe part of the cruise control ? Thanks

------------------
88 GTA 5.7 TPI Charcoal Grey Bone Stock except for loose muffler which makes it a bit louder than normal.

 

Sorry, wrong forum!

 

I have the same thing in my grand prix, it was hanging down after my fender got backed into, its supposed to bolt up somewhere behind the fender , its not supposed to hang there. Its some sort of vacume hose or something , dont know what it does, better leave it alone haha.

------------------
87' Camaro Z28
305 TPI
Stage 2 hypertech chip
Custom ram air w/K&N's
air foil
shift kit
aluminum driveshaft
posi
VST gas ryder gas shocks
3" flowmasters
custom muffler

 

its a vaccume resivoir

 

Yes it is a vacuum reservoir. It stores some vacuum so heat/ac controls will continue to work briefly after the engine is shut off. There is a check valve located beteen the vacuum reservoir and intake manifold. It is common for the vacuum reservoir to break loose from its mounting point.

 

The vacuum reservoir is installed on cars equipped with cruise control. The vacuum storage is required to operate the throttle servo under acceleration. Vacuum is required to move the servo when the cruise module commands the throttle angle to increase. When this occurs, manifold vacuum decreases, and may go as low as atmospheric pressure, so vacuum storage for servo operation is required.

------------------
Tim

1992 Z28, 305 TPI 5 speed, 12.1 sec @ 114.7 mph

1984 Berlinetta 305 TPI Auto, 13.8 sec @ 99.7 mph

 

Tim, should the reservoir hold vacuum when applied with a pump?

------------------
1989 IROC-Z 5.7L
NOS 5151 150HP kit
ProBuilt 700R4, PI Vigilante 2800 stall lockup
Baer Brakes 12" Sport System

 

Yes, the reservoir should hold a vacuum, no matter what is used to pump it down. The reservoir is a sealed container with one in / out port.

------------------
Tim

1992 Z28, 305 TPI 5 speed, 12.1 sec @ 114.7 mph

1984 Berlinetta 305 TPI Auto, 13.8 sec @ 99.7 mph