Lumbar and Bolster

[Deathacus]

Hey there! Decided to start a new thread since all the ones I found are pretty old.
As not unexpected, I'm having some issues with the inflatable stuff on my seats. Everything will inflate just fine, but the drivers side bolsters deflate over time. Not super quick, they might go down just a tad between here and work but might take a couple days to fully retract. Occasionally, the lumbar will also inflate slightly while adjusting the bolsters. Couldn't tell you if they leak out since I keep that all the way down anyway (I don't care for a hard back). As for the passenger, it seems to have held just fine but inflating one leaks a lot into the other. Plus the power track doesn't wanna work when the car isn't running. I checked the air lines running near the back hinge and they don't seem to be rubbed open, as others have suggested. I'm a bit nervous trying to take it apart and tbh the service book is not set up in the most user friendly way.

 

[luigisho]

This is tricky. I only remember a few repairng this over the years. I always just left mine alone. Usually a leak but tracking it down never seemed worth it. Sometimes cleaning the track and relubricating it frees it up a bit more. Gets a good build up of grit and grime over time. Also we never got the highest quality motors for these power seats.

 

[rubydist]

The line from the air pump to the bladder passes over some sharp edges of the seat frame and over time the line tends to get cut from that. Most likely if you look in the area of the backrest pivot, you will find the line is cut enough that it leaks. What I have done with the most success is to cut the line in half there and slip some vacuum hose over it a few inches in each direction. That not only seals the leak but also puts the rubber over the sharp edge of the seat frame so it is less likely to get cut in the future.

 

[Deathacus]

Makes sense. Guess I'll have to pull the cover off and see. But what would cause one part to blow up a little while I'm trying to inflate the other? Nothing seems to be leaking out of the passenger seat, just between the lumbar and bolster sections, and only while inflating

 

[rubydist]

In that case, maybe its the control that is actually leaking.

 

[NoSlo]

The buttons are both electrical switches to turn on the pump motor, and valves to open the appropriate hose to the bolster, or to vent the bolster air. There is only one pump, the buttons direct the air. Figure that 30 years later, any rubber seals or flaps are probably pretty stiff inside. One might take the control panel out of the seat, and spray some silicone lubricant in all the ports to wet the seals.

The seat rail motor is like the window regulator motors, it just gets gummed up inside, and the lubrication on the tracks dries and turns to glue. The extra voltage when the car is running adds a bit of extra power.