fan blowing to feet and screen only

[xb1977]

Hi,

I have got a VS exec and it only blows air to the screen and feet.

Have tested with another fan selector, no fix still same problem.
Works on all speeds.

Any ideas??

[VRSS]

check for vacuum leaks mate

[50LTRv8]

Spot on, under the glovebox in the dash would be my first thing to check.

There is a small block with some vacuum hoses running to it.

Turn the car on with the aircon on and find the block, feel the hoses for air leaks, if there is one try and push the hose on again.

I get the feeling I may have to replace the block in my VT because under medium to hard acceleration the aircon goes to the windscreen only


Good Luck

[hako]

The VS exec doesn't have the block like the VT - the usual cause of this problem is that a vacuum hose has been dislodged usually from the heater tap vacuum switch which is located to the left of where the clutch pedal would be....about 100mm above where your left ankle is when in the drivers seat. I've attached a pix to show to 2 vacuum lines - they have the clear plastic plug ends. If either is dislodged you will have no vent control. Ask me how I know!.

[xb1977]

Thanks for that info Hako but I have checked this, it is the most obvious and easiest place to look all was intact. Any other ideas where I can look?

[Cheap6]

It's a common fault so you should get something from a search too. One of the more obscure ones is the one one-way valve - white plastic, in line with the vac hose to the manifold in the engine bay - can leak. Kinked, cracked or dislodged vac hose, leaking vac ball under the LH guard.

[hako]

The mode selector - the switch that changes the vacuum path to direct vacuum to different slaves - this selector switch can break internally - what happens is that a plastic clip which hold the selector switch together breaks and this allows the switch to leak vacuum - there is a fix in the aircon thread and this is a post by "joe rolls commo":

Hey, I'm having the same problem with my A/C vents as other previous posts have pointed out. The problem being that I'm not getting any air-flow from the centre-face vents, d/s p/s door handle vents, or the rear passenger vents. Air is only flowing into the foot-bays & windscreen de-mister.

-I'm getting error-code #36. I thought this was inlet-manifold gasket - but nooooo.
-With the car idling, A/C on, I'm getting a hiss on 3 of the 5 positions (feet, face & full circulation) on the selector switch.
-I've pulled out the glove-box, centre-console etc and traced back all the lines, only to find they're all in position & un-damaged.
-I've traced the lines from the vacc'-tank, to inlet manifold, into the fire wall, doing the CRC test - again, all connected, no damage.
-The connection to the selector switch is complete, no probs there.
-I'm getting an air leak down where the metal coolant-pipes feed into the heater core.

I've sifted through all the A/C threads & still can't figure a solution. I'm thinking of getting a new 'air selector unit' & dropping it off to a pro if that doesn't work. In any case, I'll post the solution when I sort it.

Until then, anyone got any ideas?

***EDIT

I found the problem. The switch was knackered (knew it would be something simple). I don't have a camera handy so I can't put up the pictures, but I'll try & explain.

When you pull the vent-selector switch out, it breaks up into five parts:
-The male plug that the vacc' hoses connect to.
-A coin sized washer, with a rubber 'maze' on one side.
-A back-plate
-A spring.
-And a push clip that holds the lot together.

Cause: After I pulled the switch out I noticed that it wasn't hanging together properly. Long story short, the little plastic push-clip (like all plastic bits in a VR/VS), that hols the switch together was broken. One of the pins was snapped off on the push-clip, combined with the spiring putting pressure on the switches assembly, causing the washer with the rubber "maze" to sit skewiff.

Solution: In aussie fashion, I picked up a twig, carved it into a wedge, re-assembled the switch and jammed the peg in push-pin, which opened it up & held the switch together. So the problem was fixed for the price of a ... twig (it's now a GM twig). Alternatively, holden wanted $160 for a whole air-con console, and local air-con bloke wanted $90 check it out. Didn't get round to checkin with a wrecker.

Notch one up to me being a ****in legend!

[xb1977]

Thanks for the post Hako, what switch are you refering to?

[xb1977]

Any other ideas, still no luck.

[hako]

Thanks for the post Hako, what switch are you refering to?

The switch is the one you turn to direct air to demist/face/feet etc. They do fail.

[xb1977]

I have changed that and made sure that the vacuum plug was on it 100%

[xb1977]

Any other ideas, still no luck.

[dynoryder]

i stuffed my vac system moding my aif filter box

there is a big black sphere under the air box in the wheel arch i drilled into it

had to slag it up and it works fine

[xb1977]

Warm weather now, fan still not working properly, any ideas?

[xb1977]

any ideas what it can be?

[xb1977]

anybody know what it can be?

[88GreenVN]

have you checked all the vacuum points from heater tap to the vac ball?

[ericmo]

--- Relates to VS Commodore----

I removed the air con control from dashboard then removed the vacuum control selector from the housing. In order to get to one of the screw you need to remove one of the electrical connectors. This is done by levering the connector out as there is a small lug which locks it into the housing. The control is held in with two phillips head screws.

THen using thin nose pliers and screwdriver I carefully disassembled the switch. there is a rubber 'gasket' which has channels moulded into it for the vacuum to work, I noted that there was some dirt but also what apeared to be oil/lubricant ?? Perhaps this was blocking the channels even though there wasnt that much and I am not sure if that should be there. Anyway I cleaned it and reassembled matching the gasket and the metal plate replacing the spring then holding the cover in place pushing hard enough for the clips to go over the plate (note the plate only aligns with the cover one way) then whilst holding inplace, I replaced the plastic locking clip and twisted it into position.

When re-inserting the switch it will only go in one way as the two lugs are different sizes. Replace the two screws and reinsert the electrical connector.

After all that it worked straight away, so success for now, will see how long it lasts.