454 MPI wont turn above 3200rpm
#1
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454 MPI wont turn above 3200rpm
Trying to help out a buddy, has twin 454 mpi inboards, one engine will not turn past 3200, other fine, idles fine, runs boat on plane, just stops @3200, no mis or surge. compression about 125 thruout, new plugs, wires, fuel filter, etc any thoughts ? Thanks Rob
#2
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iTrader: (1)
I'm guessing it's either picking up a knock and is retarding the timing, or if its a MEFI 3 it might be getting a code 44 and retarding timing.
Look on the side of the block for the knock sensor(s) and see if the wire is connected. Next think make up a code reader and check for codes
[ATTACH=CONFIG]566933[/ATTACH]
#4
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iTrader: (9)
Year model and engine serial number so important for any type of advice plus what the set up changes thru serial number runs.
the list .
coil -- cap -- rotor
Possible not running on all cylinders ?
sealed inline spark checkers testing
fuel pressure testing - the numbers are thru out all rpms ?
engine scan ?
Injectors most of the time forgotten about and a lot of the times need servicing regardless.
the list .
coil -- cap -- rotor
Possible not running on all cylinders ?
sealed inline spark checkers testing
fuel pressure testing - the numbers are thru out all rpms ?
engine scan ?
Injectors most of the time forgotten about and a lot of the times need servicing regardless.
#5
Registered
I would be checking the injectors. My 502 ran fine until a certain RPM and then wouldn't go past. Did new plugs, wires, cap, rotor, filter, scan, and a fuel pressure test. Nothing caught the clogged injector and ended up with a melted piston.
#6
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[QUOTE=BUP;4550719]Year model and engine serial number so important for any type of advice plus what the set up changes thru serial number runs.
the list .
coil
BUP really enjoy all of your inputs.
Besides the magic elixir that is used for storage - I've been putting a couple of cans of SeaFoam in the initial fill-up each year (50 gallons)- I use a good midgrade fuel throughout the season - is there something else that we should consider with our injectors -- Oh I have a 454 MPI (year 2000) with about 500 hours - runs just great
thanks in advance
3pointstar
the list .
coil
BUP really enjoy all of your inputs.
Besides the magic elixir that is used for storage - I've been putting a couple of cans of SeaFoam in the initial fill-up each year (50 gallons)- I use a good midgrade fuel throughout the season - is there something else that we should consider with our injectors -- Oh I have a 454 MPI (year 2000) with about 500 hours - runs just great
thanks in advance
3pointstar
#8