Lost RPM - '06 Challenger

[Jesse]

Got a new Challenger 180 brand new in '06 and when I got it out of the marina in '07, I had lost about 1800 RPM. Runs smooth, no missing or anything, just doesnt have the power it once had.

any thoughts?

I've run all year with high octane fuel, changed spark plugs, but didn't make a difference.

 

[Skatman]

Plugs........

You say you changed the plugs.....what did they look like? That's a 4-TEC engine and if there was an operating problem with it, it should let you know. Have you changed anything like the impeller? Have you inspected the drive shaft.
Pull the plugs and remove the shaft safety cover, turn the engine and shaft by hand, see how much resistance it has.
We'll be waiting.......