1994 Supra Sunsport 5.8 Pro Boss Starting Problems

[fishga]

I have a 1994 Supra Sunsport with a 5.8 Pro Boss. I am having terrible starting issues. Upon launch, boat starts but is very hard to start. After it starts it will run fine. After it shuts down and upon attempting to start, it fires quickly then dies. It takes up to 5 minutes to get it restarted. Pulling off the flame arrestor, you can't see any gas coming out of the throttle body injectors. After a while, sometimes having to tap around the high pressure pump, fuel starts to squirt out of the injector and the boat will start.

We have replaced both fuel pumps and the fuel filter along with the fuel pump relay. Mechanics are perplexed. any help will be greatly appreciated.

[Cusefan78]

Have you changed the canister filter.

[fishga]

yes. new filter when we got the two new fuel pumps. filter is low on the port side of the engine. had dealer do it.

[Cusefan78]

Ok then find the fuel return line. Pinch it closed and see if it runs better. If it does one of your pumps was defective.

[fishga]

thanks! Will check out next time down at lake......

[Cusefan78]

Let me know. My high pressure pump went bad last year and found the part was updated and the new pump wasn't right. Had to track down another manufacturer that made the same pump