My bud has a 1994 502 415 efi at 2200rpms its fine go to 2300 rpms in gear only and it brakes up like a bad module or coil. I checked everything from grounds to fuel pres everything. Just bought the boat from a guy that said it was ready for the water. fresh eng. new stainles marine exh. and a little bigger cam. Im wondering if the new combination is causing it to lean out under load. It almost sounds like its hitting the rev. limt.

Have you seen the thread about cleaning the fuel rail?

No whats up?

I have been in the eng. compt. for a week. you name it I checked it. Everything is new or rebuilt. I checked the screens on the top of the inj. spotless

had a very similiar situation with a 500efi. no problem going to 5000 in neutral but 2700 was it under load. it was fuel delivery on mine. Actually unhooked the vacuum hose and it ran fine under load. obviously rich down low, but it ran

Did that Fri. Im starting to think with the addition of STM exhaust and a bigger cam it couldt need to be re maped.

But one thing is for sure the guy my friend bought this boat from was full of **** there is no way he put 10 hrs on it and it was ready for the water. I hate a ****ing lier!!!!!!!!!!!

i have the same set up mine never did that but i did later remap the ecu. how about the iac

That would only effect the idle.

Make sure the rotor is not moving around. Might have to put some lock tite on it.

No just got all the elc. isues fixed no we have no fuel pres. with 2 new pumps wtf!!