Need to know what I need to fix and how to fix if you know and can help, I'd appreciate it, rainy season and window stuck down, so need help ASAP.

A mechanic told me he would look this up for me. My car makes a whiny sound.

I usually drive a standard truck but i was driving my automatic and my passenger jumped out and the shifter must have moved or i was just in the moment thinking it was a standard to slow down.. noew the rpm is screwing up and the gears.. what do i need to fix the timing belt?? please help.. thank you

My boyfriend's nervous dog ate through my passenger seat belt.

How much would it cost to replace? There have been people in online forums who have said they've been quoted 300-400 dollars... but said a DIY would run around 40 bucks for the belt. Help!

I want to reset the "change oil" light.

Where is the BCM located on my car and what would it cost to have it replaced?

Front O2 sensor original, does not test bad.
Rear O2 sensor tests bad.
If I replace the rear sensor with one from Carquest will it affect engine performance?

My timing chain broke and the mechanic found that there were problems with the valves on the engine. I was debating whether or not I should even get the car fixed because it is not worth that much. The mechanic told me I should replace the valves and the timing chain and then it would be like I was driving a car with a new engine. After getting the car fixed at a hefty price ($2700), I found that it was leaking oil. I took the car back into the shop and the mechanic said that some of the O-rings are bad and it would cost another $3000 to fix the problem. Does this seem right to you? The dealership by my house says that if they went in to my car to replace my timing chain and they found that there were problems with the valves, that they would then recommend that I also get the engine replaced and that they wouldn't recommend just fixing the valves like my mechanic did. I'm also wondering, can a mechanic be able to tell if there's a problem with the O-rings when he's replacing the timing chain?