Vacuum central locking

[trauts]

I was trying to sort out my central locking not working on my car, so i located the vacuum pump in the boot. Found it had been disconnected and reconnected it.
It started pumping.. sounding like a fish tank for a little bit.
My car was locked, so i tried unlocking it, and it was a struggling to unlock it.
So as a test i opened all the car door locks, and proceeded to the drivers door to lock it but it seems the pump already sucked all the doors down already, and would not unlock them. and would not unlock the boot easily.

What do you think the issue could be here.
it's as if the vacuum locking is always applying suction to lock the doors.
I don't think there could be a leak.. but then again i have no idea what the issue could be.
Has anyone had this happen to them or know what could be causing this.

[h100vw]

The pump will run continuously or intermittently (not in response to a key) if there is a leak in the system somewhere.

If that is the case it would be best to isolate parts of the system and hunt the leak down. There's is obviously a solenoid in each door and for the fuel flap.

IIRC the pipe runs under the back seat and splits to each side and runs down the sill. Have a look there and see if you can find it. Follow to the closest joint and block it off. The pipes are rigid plastic, possibly orange with rubber tee pieces/splices at the joints.

Lock the doors and see what happens. The system is designed to maintain the vacuum once locked to keep the locks down. If the vacuum leaks away the pump runs again to maintain it. Eventually this constant running will cause the pump to overheat and burn out.

Gavin

[Golf Loon]

Usually a leak at one of the door apetures.
Lock the doors, all buttons should go down. I fone doesnt, open the door and you will hear air escaping. Under the rubber boot is a hose, reconeect it and system will work.
If pump runs for ages, it will burn out, so fix the problem, or disconnect it.

[trauts]

so best course of action would be to put all the windows down, lock the doors manually?
if one does not lock then it should be the location of the leak?
what about the boot? another possible leak location.
The pump was running, when I was not trying to lock it.. i thought it was building up pressure or something.
But now realise it was a leak.

[cicca_294]

not to bomb this thread or anything,
but what's the deal with mine taking it merry time when i lock it,
somedays its immediately, others, its like 5-10 seconds after i've locked it?

[camhaz]

so best course of action would be to put all the windows down, lock the doors manually?
if one does not lock then it should be the location of the leak?
what about the boot? another possible leak location.
The pump was running, when I was not trying to lock it.. i thought it was building up pressure or something.
But now realise it was a leak.

Lock the car and put your ear near the lock of each door and you might hear a hiss of air escaping, that's how I traced it on mine. Start with the driver's door as this is most likely to be the culprit.

[Garbon]

I have this problem now, it is in the B column drivers side rear door.

I took it apart however there is a black connector which is at the end of the blue air line tube which has snapped off.

Where do you get these black connectors from? It goes something like blue air hose connects to black connector in the B pillar which then attaches to another black connector in the rear door. ie these 2 black connectors marry up to each other. Both black connectors sit inside the grey housing which is attached to the door pillar..

Any ideas?

Thanks

[h100vw]

Volkswagen o a breakers yard for spares. Are we still talking about a mk3?

Gavin

[Flat-Mango]

I had OP's problem, found it was the fuel cap.
All the mk3's fuel cap actuators at the wreckers were broken, but the Seat Ibiza has the same part. Swapped them over and all is well again..... for a month. The same leak in the same place. Gonna try a air tight glue around the seals to solve it.

EDIT:Blu-tak at the T-pieces fixed it for me.

[Garbon]

Yeah still talking Mk3, tried Austral VW in Brisbane and a dealer in Sydney, they do not know what it is.... I even sent them a pic of the part to try and source it. If I go to a wreckers it maybe as brittle when I try to remove the black plastic piece on the end of the blue air hose... Maybe worth a try though. I guess I could just by pass the 2 x black connectors and use some rubber tube between the two bits.