Check your inlet screen on the mixer where the propane comes in from the vaporizor..there is a small screen that can get clogged woth debris...be careful,it is held in with a small clip and the screen can rip easily

DTC E36--LPG Fuel Pressure sensor diagnostic result signal.
Check fuel pressure with Diagnozer. If pressure is reading low then retest pressures using actual gauges to confirm pressure. If actually low, check fuel lock and filter (clean).
If no reading, check failed main C or EGI relay, blown fuse, broken wire at the sensor, blocked filter screen in the injector holder.