Working on a new to us 2019 95-2 Kubota We replaced the engine because it had no oil pressure. Misc tribulations, but finally got it running. Deleted DEF system. After running a few hours, it threw code 9302, air in fuel. Restarted and ran fine. Several hours later, it's back in the shop, because it will not start reliably hot Problem seems to start once machine is warm. Also codes when engine is revved several times consecutively. It may die then. We checked all connections, seem good. Replaced line to tank, no change. ran on a diesel can. no change. bypassed fuel water seperator, no change. re-attatched f/w seperator. bypassed fuel filter. No change. The only thing we have not bypassed is the lift pump itself. Seems to be a suction on the fuel filter when it dies. Pump is pumping fuel. Anybody see this before? Machine runs good except as noted.
Could there be a problem in the injector pump or beyond that would cause it to throw code 9302? There are no visible leaks on the machine and the fuel system is good to the injector pump. We swapped the old fuel system onto the new engine. The machine runs perfectly fine working. If I rapidly rev the engine 4-6 times it throws the code, and dies, or derates itself. And it is not reliable on hot starts.
Is this something an injector sticking open could do?