general problems of the 2006 Suzuki Reno

So I park my car in the drive way turn it off and take the key out but the car didnt turn off. . It was still running. It turned off when I opened the door, the lights on the dash all stayed on. This happened numerous times. I've had this car since 2006 and have had my share of problems with it. . Before this happened I was having issues starting it for about a week. . Maybe longer. I would have to start it about 3 times before it stayed on.

The check engine came on, and I had a diagnostic done. It showed one O2 sensor was not good. It was replaced. After one week the light came on again, and another sensor needed to be replaced. About two weeks later, the light came on again, and the test showed that the catalytic convertor needed to be replaced. This was replaced. Two months later the light came on again, and it shows that both the O2 sensor and catalytic convertor need to be replaced. Nonetheless, the car passed the emissions test, but the light is still on, and the diagnostics still read the same; the O2 sensor and catalytic convertor need to be replaced. The acceleration now has problems. Sometimes, the car will hit 3-4 rpm while the acceleration is at 40 mph and will not go higher. Sometimes, I have to pull over because a "burning rubber smell" is emitted from the engine and comes into the car through the vents. The mileage now is about 96500.