throttle cable/linkage troubleshooting help

1996 Nautique Super sport....
So something strange happened suddenly today. Halfway through the day my wife claimed the boat had zero power and would not move. When i checked it out, that wasn't really the case, and i got us back to the dock.
When the throttle lever is moved forward or backward into the 'first click' position, the boat clicks into gear and idles forward like it should. Now when you go into full throttle is where the problem starts....if i push the throttle up to its usual full range of motion, nothing happens. The motor doesn't rev up the slightest bit. It gets no gas. But if i keep moving the throttle past its normal full range, the boat powers up fine. When i say I move the throttle past its normal range, it is pointing to the ground 180 degrees from neutral. The lever never moves that far.
Whats the best way to troubleshoot this? Cable? linkage at the throttle or engine? I would expect cables to either seize up or break. Could the cable be starting to fray internally? I can see this troubleshooting getting tedious on my own with having to move the lever and run around the boat trying to find the issue. I was hoping someone could narrow it down for me.

Thanks a lot

It sounds like the throttle cable isn't secure on one end or the other anymore. So basically, through the normal range you're just moving the whole cable assembly (rather than just the inner cable) and then finally getting any slack out of the cable and getting some movement from the inner cable when you go past your normal range. Check each end to make sure the outer jacket is secure and not slipping through the mount.

Do you have perfect pass?

putting it in gear is a different mechanical mechanism than pulling the throttle cable. I don't remember for 100% sure, but I think there might be 2 cables (one that puts it in gear only and the other that actually pulls on the throttle lever on the engine itself.

If you have perfect pass, it could be as simple as the rope has gotten unwound from the servo motor. sometimes this is because the motor's starting to fail. Sometimes it's because the throttle was pushed harder than "fully extended" and it unwound the cord from the perfect pass servo.

Yes I have PP, and I think that's the problem as I can't find anything wrong at this point. It seems like the servo failed to wind up. Either it's going or I'm having a low voltage problem to the dash where PP is wired to

Originally Posted by mro

Yes I have PP, and I think that's the problem as I can't find anything wrong at this point. It seems like the servo failed to wind up. Either it's going or I'm having a low voltage problem to the dash where PP is wired to

you can go into perfect pass and test the voltage getting to it. Hit menu and the up arrow at the same time. That should get you the menus where you can get system info. It's the same place that I have to scroll through to get the water temp.

Get a volt meter and test the voltage at your battery. Then power on the PP and see what kind of voltage the PP gauge is reading. if it's a big difference between the two, you've probably got crappy wiring between the battery and the PP. On my 92 Supra, I ran a good clean power and ground just for the PP and it cleared up a lot of the problems I was having.

Found it. Broken ground! It looks like the wire cutters accidentally got the ground at some point. It broke in 2 when i was following it.

There ya go. Perfect pass it is. Glad I was able to steer you in the right direction.