Hey guys. I got a Mitsubishi forklift I have to get the model number but I'm overly frusturated.

The guys were using it and it "ran out of propane" so they put on a new tank & it hasn't ran since.

We tried a few different tanks yes. Including one off of a known running forklift.

It has a little 4.3 Vortec on it (as appears to be)
A couple of the local companies came to try and fix it.
Cat put it on the computer and said it is not a computer issue.
The machine starts, runs rough, and dies after about 10-15 seconds.. the local repair companies have charged a arm and a leg for a new distributor. A new "mixer". A new electronic throttle petal and checking computer issues.
If I start it like I said runs rough for 10-15 hen does. Will NOT restart unless key is turned off and you wait a while.
OR
Once it shuts off I pull the main power ecm fuse from the fuse box and put it back in.. then it will run for 10-15 again.
I can get it to stay running if I rev it up to about half throttle but it stays running horrible and backfires.

I also tried a bypass on the fuel lines straight to the fitting on the carb to eliminate the "filter" and the shutoff valve.

I'll get the model number and year for it but for now maybe someone has had the same issue.