99 200EFI Dead in the water

[mibeb34]

I recently bought my first Mercury (1999 200 EFI, 0G840098) knowing that it had been stored for an unknown period of time. I emptied the fuel, cleaned the VST, replacing the fuel pump, fuel filter, lines and anything else that held old gas. I started it connected to a water supply and it ran. I ran it about 2 hours the first time out with no issues. The second time out started great. I ran down the lake about 8 miles at ~55mph with no issues. When I sat down to start fishing the motor stopped and has not started since. It will turn over, but does not fire. I'm thinking fuel pressure regulator, but I wanted to post to see if anyone had seen this before I drop $300.

[Jwilley]

Have u checked for spark? Kill switch didnt get bumped by chance?

[mibeb34]

I did. I actually changed the plugs while on the water. Verified spark when back on shore. Kill switch still in position.

[Jwilley]

Can u hear fuel pump turn on? I think computer sends ground signal to turn fuel pump on. If u dont hear pump turn on when key is on run jumper wire to ground side of fuel pump harness

[EuropeanAM]

Can u hear fuel pump turn on? I think computer sends ground signal to turn fuel pump on. If u dont hear pump turn on when key is on run jumper wire to ground side of fuel pump harness

Before you start altering the wiring- verify that the pump DOES or DOES NOT function with the key turned ON.

If it DOES NOT function, verify that the ECU connector is intact, firmly and properly connected with a good locking ring, and locked into it's retaining bracket. Also verify that the GROUND wire for the ECU is intact and properly connected.

[mibeb34]

Thanks for the input all. I'm not sure if the problem resolved itself or if this simple find was the real issue. I checked the fuel pump and had good pressure there. The fuel pump was new (I had recently installed), but remembered while I was removing the fuel pump I saw a small split in the small (vacuum??) line coming into the top of the fuel pressure regulator. I cut the split out of the line and replaced it and tried to start the engine. It fired immediately and has not missed since. Could it really have been this simple?

[EuropeanAM]

It would have made the fuel pressure higher than necessary at low RPM's (causing a rich condition at lower RPM's and idle).