Bamacrusader
Recruit
- Joined
- May 30, 2015
- Messages
- 3
I just bought a 2003 Sea Pro with a Yamaha F115. The previous owner had everything tuned up before he sold it to me. However, the boat will not get over 3000 RPM's when in gear. It seems to idle fine and run well in neutral, but not under a load. All filters have been replaced within the last month. I personally drained all old fuel out and put in 15 gallons of pure gasoline. Fuel pressure is a steady 41 psi. All spark plugs are firing. However, the #4 spark plug looks brand new after running, while the other three are blackened a little, but not fouled. I also replaced all 4 fuel injectors. I used a simple, basic test light to see if all my injectors were getting a voltage. All four of the red/yellow wires feeding each injector light up the test light like it is getting a good 12V to them. The top three injector wires that are purple/striped, light up the test light, but the test light is dimmer than it was when probed on the red wires feeding the same injectors. When I test the probe on the light purple/green striped wire feeding the fourth injector, the test light does not come on at all.
So, I have come to the conclusion that my fourth injector is not getting the signal to open/close like it is supposed to, and no fuel is entering my fourth cylinder. And that is why the spark plug for my fourth cylinder looks brand new, even after running the engine for several hours. I traced the wire back to the ECU. The wire is not damaged and has continuity from the injector back to the ECU. Does all this mean my ECU is bad? Or could something else be causing the injector not work? Thanks in advance for any help.
So, I have come to the conclusion that my fourth injector is not getting the signal to open/close like it is supposed to, and no fuel is entering my fourth cylinder. And that is why the spark plug for my fourth cylinder looks brand new, even after running the engine for several hours. I traced the wire back to the ECU. The wire is not damaged and has continuity from the injector back to the ECU. Does all this mean my ECU is bad? Or could something else be causing the injector not work? Thanks in advance for any help.