Recently purchased a 2010 Nissan 30 forklift (MCP1F1A15LV) with the K21L Lpg engine. Previous owner said it "shut off" and wouldn't restart one day and he didn't want to be bothered with it (he had multiple brand new Toyota lifts so this was an 'extra'). Found a broken battery terminal, fixed it, put in a new battery, strapped a tank on it and it fired right up. Used it a few times with no issue and the it popped an E-28 code (cam sensor) and began stalling out on occasion and then one time it wouldn't restart. Let it cool off and it would start and run for about a minute and shut off. So I ordered a new cam and crank sensor and installed them along with new NJK spark plugs. Started once, ran kinda rough and shut off, never started again. Wouldn't even fire on starting fluid and also kicked an E-27 code as well now. They were cheapie sensors so I ordered Nissan sensors (might be fake, got them online), part# 23731-AL60C & 23731-6J90B. Installed them and it still wouldn't start. Gave it a quick shot of starting fluid and it fired right up and ran beautiful. Thought it was fixed, but no. Shut it off, won't start. If I keep trying and trying and trying (multiple key cycles), sometimes it will fire and run fine. But usually have to give it a quick shot of fluid for it to fire. It will run all day perfectly fine as long as you don't shut it off, but once you shut it off you need starting fluid to get it restarted usually. I'm at a complete loss because it's obviously getting fuel and spark, and I did a compression test and it's 190# across the board. I don't know a lot about Lpg engines, so I don't know what to look at as far as fuel. But it wasn't doing this before the sensor went bad. And it's not throwing codes for the sensors now so I would assume they're working properly. Any thoughts?