2004 Evinrude 225 DI

[tnorth]

My engine will not get above 4000 RPM's at WOT and will only run around 45 MPH. I have replaced the spark plugs, plug wires and cleaned the filter at the VST, plus cleaned the screen for the electric fuel pump. Any ideas on what the problem could be. Motor runs great otherwise, just NO top end at all. Thanks,

 

[Boobie]

Do a cylinder drop test on it to see if it's running on all cylinders.

 

[kevinj]

Are there any check engine lights? Your issue could be a throttle position sensor problem but you really won't know until you connect it to EVDiag and determine if there are trouble codes or if your TPS is out of spec.

KJ

 

[faztbullet]

Also run a compression test....

 

[tnorth]

There are no warning lights or alarms of any kind. I had DFI check the EMM and everything checks out great. On the water hose/ ears, the engine will rev up as high as you want to go but on the water will not go above 4000 RPM's. I will be taking it to the shop but I know it will be hard to duplicate unless its in the water. TN

 

[Boobie]

Read post # 2 again !!

 

[daselbee]

The easy and proper way to do a drop test on it is using the Ev Diags Software.
You can shut down individual cylinders while underway, all the while watching to make sure each cylinder has the same affect on the motor.

 

[tnorth]

Thanks for the suggestions. I will have the shop hook it up and check.

 

[Boobie]

And if you don't have any Ev Diags you can still pull plug wires with an insulated pliers.