My Hyster fortis 60 is throwing a fault of 522655-1. It seems to run just as it should and I can clear the fault, but after driving for a couple of minutes the fault returns. There is no hesitation in the drive or idle or anything. The operator claimed the cab filled up with the smell of propane, but I have yet to notice that smell, so i'm not sure if that is accurate. I have seen other forums where people had this fault and also idle or running issues, but I don't seem to have anything with the operating part being an issue. Any advice?