1995 Ford Escort lighting problems

Since we bought this used program vehicle, we have had to replace the tires at least 4-5 times, the back top brake light numerous times (fuse) the brakes at least twice and when my son was hit during the winter the airbags did not deploy and he had back injuries his passenger had chest pains from the seat belts, we did replace the timing belt this year and than in july the engine stopped working and the mechanic (pride auto) stated that the engine was damaged this occured while driving appx. 25 hrs per mile.

When on highway 55 MPH or more transmissions acts like it goes into neutral have no overdrive or drive then also slips in and out. Also have like power surges when using the heater in the car the engine revs up and down like you are stepping on the gas pedal even when in park have not been able to find the cause of these issues yet.