Recreational Vehicle Lpg Tank Valve/gauge problems of the 2008 Chevrolet HHR

I purchased my Hhr 2008 new and only have 34400+ mileage as to this date, not hard on braking and 2013 the brakes were warped and I have it repaired. I experienced the problem with the ignition once, cannot turn off but after trying it eventually turned off after several try. This happened only once so I did no¿¿t take it to the dealer. Then my power steering went out while I was driving 40mph, I stopped the car and called the dealer and advice me to bring it in . The steering assist motor was replaced in 9/1/11. Then Nov. 19,2012 the rear side door will not close. My daughter have to drive while I was holding the door close, dealer replaced the internal lock door. Now I a¿¿m having problem with the engine light warning on with the temperature gauge working sometimes. I took it to the dealer and they said that is was not on. So nothing was done . As I said it work sometimes and most of the time it was¿ not working. I will take it back to the dealer and hopefully it will stay on so they can check what's wrong with it.