A wet floor indicates one of two things; either rain water or coolant.
Press a paper towel into the wet spot on the floor / carpet. If colorless, it is likely rain water that has entered through an open window, an opening in the sealant between the windshield and the body opening for it or an opening in a seal between panels of the firewall.
If there is a green, pink or yellow tinted color, it is probably coolant. If it feels slippery between your fingers and has a "sweet" smell to it that further suggests that it is coolant. A check for lowered coolant level in the radiator / empty reservoir can all but seal the diagnosis.
The leaking rain water can be tough to find if the source is not immediately and plainly visible. If it is a coolant leak - it is probably coming from the heater core - as it is the only place coolant enters the cabin. The leak in the heater core *may* be able to be stopped by adding some of those "radiator stop leak" additives directly to a cold radiator. More often then not - the heater core will need to be replaced. The cost of this job can vary significantly based on the amount of labor required to gain access to the heater core itself (often it is buried up and behind the dashboard - requiring a large portion of it to be removed).
Below is the process for a 2003 Passat.
This is nearly always a job for a trusted mechanic. Good luck!
No, the immobilized does not prevent key removal. You just have to ensure you are turning it all the way off, in park, with the brake on, and the steering lock is not hung up by something like wheels on the curb.
The key can't come out unless you have it all the way off. Sometimes the steering lock and brake lockout prevent that, so wiggle the steering lock and push on the brake while trying to turn it off. You also have to be in park if automatic.
Fuel pressure is regulated by the manual valve on the end of the rail, and you can recognize it from is 1.5" round appearance, with an in and our fuel line, and a small rubber vacuum hose going to it.
But first you put a gauge on the fuel rail. Should be around 30 psi I think? More when you accelerate, because the vacuum line is supposed to make it do that.
But your problem is more likely the ecu is in limp mode, due to some error condition it thinks is dangerous. Is the check engine light on? Seems like it should be? Have a free read done at any parts store.
I presume you are asking if it is ok to install a second hand stearing column.
Having dealt with before, I would say yes - but.....
Make sure it is for the same year and model - close may not work
Before installing the new stearing column, take the time to lubricate it.
Make sure there are no broken or frayed wires.
Check the shift lever to make sure it is moving properly in all directions.
Before removing the old column, put a rust release agent on all bolts and nuts - I use PB Blaster
Take your time doing the removal - don't break any of wiring connectors.
Once you have the old column out, examine the points where the shift lever from the column connects to the levers or cables that go to the transmission. There are usually plastic caps or rings in these connections. I generally replace these while I am in there. It helps to tighten these connections up and reduce sloppy shifting.
Reassembly should be pretty easy - just reverse of installation. Again, take your time. Use zip ties to keep wiring up. Make sure there is nothing catching on the moving parts (wiring sometimes drops down and gets caught - nothing like a dash fire while driving down the road!!).
Snug the nuts and bolts by hand so you can adjust the column of you need to. Once it is in place, tighten it up.
Check all the electrical when you connect it (don't check the horn it the wife is leaning against the front of the car! Made that mistake.... ).
Each vehicle is different, so there are small differences that I can't warn you about.
I hope this helps! The big thing is to take your time and double check before you call it finished. :-)
