IQRaceworks
Seaman Apprentice
- Joined
- May 20, 2012
- Messages
- 37
My buddy has a Merc Vortec 4.3 in his 02' Four Winns. It started acting up this spring as we were heading back to the dock one afternoon. It was running fine, but all of a sudden the engine started to loose power, and I also noticed that the tach started jumping around all over the place....the needle was going crazy, down to 0...then jumping up to 5 or 6000rpms. We were running around 3500rpms when all of this started happening. I was driving at the time...so I backed the throttle back down and got the boat off plane. It idled just fine. We took off again, and the boat ran fun all the way back to the dock.
Since then it's been getting worse each time he's taken the boat out. It's to the point now where it will only run about 2000rpms...anything over that and the tach starts bouncing all over the place, and the engine will loose power and die. Sometimes it starts right back up...sometimes he has to sit there and crank it for a while. Sometimes it will go all day without any issues....then all of a sudden it will loose power, and start acting up again. When it does start acting up...it will idle around all day, but as son as you get the rpm's up over around 2000 is start dieing. Very strange.
He has replaced the cap and rotor, plug wires, plugs, and recently replaces the fuel pump. I told him that I think it's some sort of electrical problem...maybe something in the ignition control module. Before he goes out and spends another $500 on one of those....is there any other trouble shooting that I can do to help him out? I've done off of the standard common sense stuff like checked all of the electrical plug connections, went through the wiring around the motor looking for any obvious problems....but I didn't see anything.
Since then it's been getting worse each time he's taken the boat out. It's to the point now where it will only run about 2000rpms...anything over that and the tach starts bouncing all over the place, and the engine will loose power and die. Sometimes it starts right back up...sometimes he has to sit there and crank it for a while. Sometimes it will go all day without any issues....then all of a sudden it will loose power, and start acting up again. When it does start acting up...it will idle around all day, but as son as you get the rpm's up over around 2000 is start dieing. Very strange.
He has replaced the cap and rotor, plug wires, plugs, and recently replaces the fuel pump. I told him that I think it's some sort of electrical problem...maybe something in the ignition control module. Before he goes out and spends another $500 on one of those....is there any other trouble shooting that I can do to help him out? I've done off of the standard common sense stuff like checked all of the electrical plug connections, went through the wiring around the motor looking for any obvious problems....but I didn't see anything.
