Yesterday I picked up my first Mercedes. After a fight with the current girlfriend i happened to be over at some my parents and the lady across the street asked me if i wanted to buy her car.

One day and I really love this car!

I've been driving it 60 miles to work the last couple of days. (round-trip)

I had no problems until today.

1. the fuel gauge is bouncing back and forth all over the place when im driving.
2. the rear passender wheel makes a high pitch squeal at speeds under 30 miles an hour.
3. she didnt want to start without me pumping the gas, and when it starts the idle is under 1000 rpms and sounds like it wants to die.

4. side note thats kinda wierd... with the key off the driver door closed the radio does not play. with the door open the radio turns back on.

If you can help please do.
I plan on fixing this car and keeping it for at least 4-5 years and I'd like to keep it in better condition then when I picked it up.

Thanks.