Sticking Brakes

I recently bough a 2001 Volkswagen Jetta TDI.
I noticed that after stop and go traffic sometime the car would have a difficult time getting back up to speed.
As if it had a lack of power or was being held back.Eventually I discovered that the brake pedal was sticking just a touch.
If I reached my foot under the pedal, I could lift it up about 1/4 of an inch. Once I did this the car is fine until I need to use my brakes
again, in which case the process is repeated.
I brought the car back to the dealer and they replaced the calipers, rotors, and pads.
When I got the car back the problem was solved but it has come back about a week later.
I brought the car back to the dealer, they looked through the whole brake system and couldn’t find any issues.
They say there are no problems with the brakes but I am obviously encountering and issue.
The dealer is stumped and so am I. Any help would be greatly appreciated.

One possibility is that the liner in one of the flexible hoses at the caliper has collapsed and is preventinng the fluid in the caliper from relieving the pressure by going back up the line.

Abother possibility is that the linkage (pushrod and joints) that goes from the pedal into the master cylinder is sticking in its travel.

Another possibility is that the piston(s) in the master cylinder is(are) sticking, preventing the return of the pedal linkage to null and preventing the brakes from fully releasing.

Try another shop.

I believe it is a problem with the linkage or master cylinder but the shop said they checked it all out. Granted it is a Toyota dealership and the car is a VW they may have no idea what they are doing in there.

They’d have had access to the repair information (through their subscription database) and may just not have been interested. They’d rather you trade it for a Toyota perhaps.

This is prestty basic stuff, not a unique system. Any competant shop should be able to look into it. First thing I’d try is taking it for a run, trying to duplicate the symptom, and checking each wheel with an infrared thermometer. If one cylinder is hanging up it’ll be hotter than the rest.

If I were unable to verify the symptoms and unable to get the MC or the linkage to stick, I might change the flex lines at the wheels just because, as they’re not expensive. But if you’re finding that the linkage can be pulled back after using the brakes, the cause should be able to be verified. The booster cannot, unfortunately, be easily discommected from the MC to check each individually, but it the problem is at that end of the system it should be verifiable with some disassembly and bench testing.

try a reputable independantly owned and operated shop.

Granted it is a Toyota dealership and the car is a VW they may have no idea what they are doing in there.

Brakes are brakes. Designs across brands differ in capacity, but the fundamental design is pretty much the same unless you’re talking about hybrids. If the Toyota dealership can’t figure out how brakes work, then they’re bad mechanics no matter what brand of car the brakes are on.