454 Mag Mpi Will Not Rev Over 4,000 Rpm
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454 Mag Mpi Will Not Rev Over 4,000 Rpm
I just bought the boat and took it out for the first time 2 weeks ago.both motors ran fine but the right motor the oil temp was higher than the other one.I removed the left manifold on the starbord engine to access the remote oil filter housing.long story short it never had an oil bypass in the block so the oil was not going through the filter/cooler.Put one in now the oil temp and pressure are fine.Now to get to the next issue.That motor will not rev over 4,000 rpm any more.I removed the manifold thought the gasket might be on wrong.Nothing wrong.Checked all connections and hoses.Swapped coil,ecu,igniter,new plugs,checked compression,fuel pressure.Bought a code checker {none}.Any one have any other ideas. THANKS
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Fireing order is good had replaced plugs,none fouled.Runs fairly well just after 1/2 throttle the rest of the throttle does nothing when you get to 4,000.Throttle plates are opening all the way.Any problems w/ignition,dist.pickup?Sounds almost like i am loosing spark voltage.Tack seems to bounce a little at 4,000 when not in gear.