I'm trying to help my brother with his 5th gen. It's been sitting for a while, and it needed a new battery. Fuel pump wasn't priming, so a new fuel pump and filter was installed. Fuel pump now primes when its supposed to, but the bike still doesn't run by itself. It turns over, and it will run on starting fluid. Fuel also comes out of the fuel return line when priming. No MIL.
So Im running out of ideas here. Fuel seems to be flowing to the rail... so bad injectors? I wouldn't bet on ALL the injectors going bad. I would have expected it to run and maybe miss but still run.
Is there a switch that controls if the injectors fires? It runs on starting fluid, so ignition seems not be the cause.
I'm assuming fuel pressure isn't that important to get it running since it runs with starting fluid sprayed into the airbox. If FP is not correct, it wont run well, but it should run even if barely.
Any ideas and suggestions would be appreciated.