02 496 mag ho power and speed loss
 

I have an 02 nordic rage with a 496 . The idle is a little ruff. It feels sluggish out of the hole and through out the mid range when I am at full throttle the motor sounds like it is getting choked off. I am only able to get about 4500rpms and i have lost about 6 mph. I changed plugs already no change. I was coming a ccross the lake last weekend it was running fine and then it seemed like it went into limp mode I was only at about 4800-4900 on the tach so I didn't hit the rev limiter.

Sounds like your running on 7 cyl's. Find a rinda scan tool & perform the cylinder induced misfire test to find which one. Then do the injector & ignition tests with it. That should get you to the issue

Ill be curious as to what you find out, just got on here today to search the same issue.

yesterday going down the lake running 50ish decided to put it down and run it a bit and was 6mph below where i should have been along with the rpm's wouldnt climb over 4200

put a fuel/water separator in it this morning and no change, sounds kinda rough around 3800 I felt the same thing, that it was down a cylinder?

Keep us posted. I wont be able to play more until next weekend anyways.

Marc