When Locking Car Vacuum pump runs for a long time

We have had a bit of freezing weather and now when the car is locked the vacuum pumps runs for a minute or two.

I did a search but didn't see anything on this. Does the vacuum pump shut off when it develops its maximum vaccum? Just wonder what is the best way to trouble shoot

Most likely a small leak.

I’d think pulling the door jamb boots and listening for a leak may be the easiest thing to check. It doesn’t require getting into the doors or accessing the pump, which would be my next step.

-Todd

Thanks will do
that. Any common area that they start to leak?

Not really. But you can isolate the doors one at a time by unplugging the harness and plugging the vacuum port. It's pretty easy. Don't forget the trunk area though.

vixentd said:

Any common area that they start to leak?

Click to expand...

Unfortunately, everywhere. Old system, old hoses.

That said, I generally start with areas the tubes get flexed aka at the door jams, and sometimes you can even hear the leak.

Fingers crossed for ya!

Well as soon as the door locks are activated each door locks, including the fuel door and trunk. The motor still runs for about 30 seconds or more. My ears have not been able to hear any leaks.

I have disconnected the front door and had some trouble screwing the large nut back on to make it seal tight.

Tomorrow will take the trunk passenger side off, and see if there is any leakage at the fuel door.

Well there's a leak somewhere, otherwise the pump wouldn't continue to run the way it is.

You could disconnect all four doors at the pump, plug the lines and then run the pump and see if it quits earlier, if it does then you know there's a leak. If it doesn't then there's a question of whether something inside the pump is leaking or damaged.

Good luck, hate tracking down these problems when the interior is still installed. With all the stuff out this is much easier to locate and fix. My wagon had leak in nylon hose running to front passenger door due to mice. With everything out it was easy to find.

Steve

Yup, the system will still lock and unlock properly with a small leak, but the pump knows about the leak and will keep on pumping till it times out.

The pump times out to prevent the battery from being drained flat, should a leak develop when the car is unattended for an extended period.

be careful with the door lines...one of mine had the nipple break, so I had to plug it...now that door is manual lock only...

Those can be swapped out but you have to remove the trim surrounding it.

Solved. The problem was the fuel door actuator was leaking, just enough for the pump to continue running, but the lock mechanism still worked on the fuel door. Luckily while playing with the lock and unlock function I wiggled the actuator rod and motor shut off.

Was able to find a 1995 Passat actuator which has a different fitting for the air line, so just cut the air line and used a piece of hose from the injector return lines, and now everything is working.

Thanks for the suggestions everyone.

Glad it was an easy fix. Those little issues are annoying and drive me crazy.

-Todd