BF130 No Fuel, ECU?

[jasonDW]

I'm going to make this as short as possible...

Motor is bf130 / yr 2000 w/ 300hr - motor has updated fuel pump and new relay.

The problem started when my main relay was sticking. Motor was running fine but relay would keep the fuel pump on after I shut down the motor. Replaced it with a new relay and no power to the fuel pump. I took it back for another relay and same problem.... The motor DOES fire when I put the old relay back on.

So my problem is no power to the fuel pump. I did check for spark and it is there.

I found out the grounding the lg/r wire on the relay will start the fuel pump and fires the engine. I have checked the grounds on the ECU and all is well. I have also tested for codes and I get nothing, only the solid light telling me all is well.

My question is can this problem be caused by the ECU even though I am getting fire and the ECU is displaying code?

Is there a way to check/test the ECU? I do not want to purchase one if this is not the problem.

Any suggestions would be great!

 

[cp]

Re: BF130 No Fuel, ECU?

I do not believe the ECU is at fault.

Looks to me like you do NOT have 12v coming in to the wht/yel wire to your new main relay (the round connector, lower left quadrant). The source for this 12v is the same as that which powers the fuel pump via the relay so it's available, just not getting to the wht/yel wire. The wht/yel wire (relay side of the round connector) is provided power schematically by a wht/red wire, which is connected - somewhere - to another wht/red which is the power to run the fuel pump.

Since the old main relay does run the fuel pump, I recommend you closely examine the two main relays (old and new) to discern if the old relay may have a connection/jumper between the wht/blk and wht/yel wires on the back of the round connector. In other words, see if you measure zero ohms between the lower and upper left quadrants of the round connector on the old relay, but not on the new relay. If the old relay has continuity between the wht/yel and wht/blk wires and the new does not, then that is your problem: you are missing the jumper connecting the two. I suspect that perhaps some, if not all, the old relays had the jumper 'internal' to the relay, while the new relays 'expect' the jumper to be in the 'external' wiring harness.

Please post the results of these checks, so that all may benefit in the future. If the above is not clear to you, let me know and I will give more detailed rationale.