Problem above 2500 RPM
 

I ran my Formula (454 MPI Magnum) around yesterday with no trouble whatsoever. After the run I yanked it onto the trailer and up to my buddies place about 80 miles away. I launched this morning and all was well pulling out if the creek, but as soon as I throttled up the motor would lose power and return to idle. I tried this over and over while underway and stationary in neutral. I found that I could sustain running at around 2500 rpm no problem, but as soon as I goose it anything above that the tach starts bouncing around and the motor stumbles back to idle, ready to start all over again.

Other than the trailer trip the only differences between yesterday and today are 1) I filled it with gas. 2) there were some wild thunderstorms overnight with occasional downpours.

Anyone got an idea where I should look?

if they are the 454 efi's i would check the vst tank screes they always get block and will do that. i had this happen to both mine this year, easy free repair....but if you dont have the old style efi then id look at other stuff

Check the level in your drive bottle. If it is low the engine will go into protect mode.

Just a stab in the dark but you might pull off the dist cap and see if the contacts look look dirty.. If so scrape with a flat head or replace.

Chris

Look at this thread and video and see if yours does the same thing.

Mine was the distributor.

http://www.offshoreonly.com/forums/g...il-change.html

Did this happen after you fueled up? I wonder if you got a huge load of water in your fuel?