I have a 2009 Avalanche C4. I'm currently experiencing an issue where the motor is non-responsive to the throttle unless I give it full throttle. The motor does not stall out and idle's fine and does not have a misfire and does not die at any point through the process.
When the throttle is pushed forward the boat takes off. However within 2-3 seconds the power cuts back and boat idle's back down even with the throttle engaged. When it does this during the 2-3 seconds the motor idles up it also engages the prop. However as soon as the motor idles down the prop also disengages.
If I throttle the boat all the way up the boat will take off and run at top speed. However any throttle position other than wide open the boat will not raise the RPM's and does not engage the prop other than maybe the first 2-3 seconds. After that the prop is no longer engaged and the RPM drops down to idle speed around 800-1000 RPM.
Has anyone had any experience with something similar to this? This issue did not exist last year prior to winterization and is something completely new. The only thing that we have had done to the boat new for this season is we had a new amp installed and head unit installed for the stereo system. Outside of that the boat is exactly the same as last fall when we pulled it out of the water.
Thanks in advance for any guidance here.