I have a 2004 Mercury 80 horse power jet with Tiller handle. The throttle was sticky and hard to throttle for a while now it won't accelerate at all. The motor starts and runs great but it won't accelerate when I turn the handle. I took off the engine cover and I can manually accelerate the idler on the motor itself. The weird part is that when I do that I can actually turn the handle it will idle down. Any advice you could please give me I would SO much appreciate. Thank you so much for your time and help.