2006 Merc 350 MPI engine - Power surging at any RPM & can't reach max rpms?

[wavehogger]

This new motor and out drive pkg was put in a 1994 21' Chapparel last summer. It ran almost perfect last summer but did seem to have a slight surging problem at only the top end around 4900 rpm, where you could feel it holding back off and on. Now the rev limiter doesn't kick in until like 5100 and I tested that last yr by trimming way up just to make sure it wasn't that. My mech put the boat put on Merc diagnostics this spring and nothing showed up. Now just today the problem has gotten horribly worse. It now surges at any rpm and won't rev up over 4500 rpm at times, very sad. My Mechanic said it tested out perfect and see's nothing that could be causing this. Anyone heard of this problem with the 5.7 MPI? Ideas anyone? Would there be a fuel filter somewhere either at the carb or inline that could be clogged? It feels fuel starved to me but maybe it's ignition related by the computer.. Thanks, Steven

 

[Don S]

Re: 2006 Merc 350 MPI engine - Power surging at any RPM & can't reach max rpms?

Had a TBI system surging last year. Turn out to be the wrong kind of hose clamps used on the fuel lines and fuel valves going to the tanks (had 2).
Found the problem using this method.

http://forums.iboats.com/showthread.php?t=167561

 

[Coors]

Re: 2006 Merc 350 MPI engine - Power surging at any RPM & can't reach max rpms?

filters, bad gas in tank...change all of it.