How to locate problem

Engine light came on
Had it checked code come up showed problem with #3 spark plug.
When we checked found water in #2 and 3 spark plug wells. What could cause that?

looking for ratio to purchase differential for car - door sticker shows axle code is 96 but cant find ratio anywhere online - Loud bumping noise coming from rear of car when driving along time or turning a certain way

Also while starting to drive it ,some times it seems to hesitate while giving it some gas is this both an transmission problem and is it an easy fix thank-you hopefully I'll hear back from someone

When driving in the highway, a lot of noise is heard inside the cabin.

When in parking, the intensity of the cabin light changes. It gets bright for a second and then dim for another second. It continues until I start driving again.

When stopped in a light or when in parking, the car vibrates and the console makes a lot of noise.

It has done this several times and now it won't start at all.

how much would it cost to fix and what is the problem

My Ford escape Jeep is not moving when put in reverse but drive moves

It was running good parked for the night and now when I try to start it all the lights come on ,windows and door locks all work but it does not do any thing ,I checked the fuses and breakers all good ,battery has full charge. Help please ASAP thanks

The light was never on before. vehicle ran prior. A dealer diagnostics is how issue was found. 2 codes, ECU and ignition coils.

My sister used my car for a year and she used home made cd's and after I got the car back the CD player doesn't work any more! Like when I go to load a disk it just say cd error!