My 2000 Volkswagen Passat stalled out at a stoplight the other day, and now the clutch won't disengage when I push the pedal down, so I can't get the car into gear. The pedal also won't return on it's own, it just stays pushed all the way to the floor board until I reach down and pull it back by hand. Is this a problem with the clutch itself or something more simple like the hydraulic line or throwout bearing?

Check the stoplight switch. Its a little switch tha connects to the brake pedal shaft under the dash (usually). It may be unplugged, stuck, or just went bad.

If you're talking about an hydraulic clutch system that uses brake fluid:
1. Fill the reservoir with clean brake fluid.
2. Have an assistantpull the clutch pedal up and leave it there.
3. Locate the slave bleeder - the slave is connected to the master, is located on the transmission housing and pushes the clutch release lever).
4. Open the bleeder and have the assistant push the clutch pedal down.
5. Close the bleeder.
6. Make sure there's plenty of fluid in the reservoir
7. Repeat steps 2-4-5-6 until brake fluid comes out with uniform pressure from the bleeder. Non uniform pressure is sign there may be air in the system.
There should be good pressure at the pedal now in the up position. Pressing it should disengage the clutch.

Bleed the slave cylinder

in no air or leaks in the system
replace the clutch

It appears that the clutch is not releasing properly when you push the pedal down. How much free-play does the pedal have when you start to push it down? It should be about 3/4 inch or so. With the engine off and in first gear, have someone push the clutch pedal down all the way while you try to rock the car back and forth. If it is trying to turn the engine while you do this, the clutch is either not capable of being released or the clutch hydraulic system is delivering insufficient oil to the slave cylinder at the clutch release arm/shaft. If this worked correctly before the new parts were put in, the person(s) that did the work should be responsible for getting it to work again. Make sure that you don't have several floor mats that are under the pedal thus preventing full clutch release. Hope this helps!

master/slave cylinder

sounds like a problem with the hydraulic clutch, either the master or slave cylinder was bypassing fluid and causing the low pedal.

Since you have already tried the obvious look to make sure that the new switch is properly engaging when you move the pedal. Most of these switches have some adjustment in their placement. Otherwise search through the wire harness and tape up ANY cracks or breaks in the plastic coating. Also look at all the connectors for green corrosion. If you find or suspect corrosion replace the connector. VW''s are picky when it comes to corrosion and breaks in wire insulation. Hope this helps.

Try pulling it back? The only thing this sounds like is a faulty pressure plate,It will roll in gear?

The fuel pump relay will cause a stalling or no start condition. You are likely having mass airflow sensor, fuel pump, or fuel pressure regulator issues.

Bret
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