Logo

2009 200HP E-Tec: Erratic RPMs when on plane. HELP!

bperagallo

New member
Hello All,

For the last year or so I have desperately been trying to get to the bottom of this erratic RPM issue I am having when on plane, however, both Evinrude service department and my certified mechanic have come up with nothing. Here's the situation:

I will be running on plane (typically around 4200 RPM) and all of a sudden the RPMs will drop down to around 2000 for a second then immediately jump back up and down again. It is a bucking type of feeling as the engine can't hold its RPMs. However, this doesn't always happen. One day I will take it out (normally when my mechanic is on board, of course) and the engine preforms perfectly without issues. Other days, the erratic RPMs are in full force and I am forced to return back to dock. Through experimenting I have determined that the engine will not "buck" if i have a full or nearly full tank of gas (3/4 or greater). Anything less than that I run the risk of experiencing the erratic RPMs. In addition, my fuel gauge has now failed which may or may not be a clue. My mechanic has recorded a PDF of the engine functions when experiencing the issue and everything seems to be normal with no codes showing. It also should be noted that at slower speeds (2000 RPMs or less) there are no issues.

Any insight into this issue will be greatly appreciated!
 
Others will chime in but could be trying to go into SLOW mode from a faulty temp sensor in one of the heads? Try disconnecting the leads from the sensors leading to the power pack and see what happens.
 
Since you don't mention it at all, I will assume there are no codes.
If so, then the thing I would do is put a fuel pressure gauge on the output of the high pressure fuel pump.

The fitting is already there, just attach gauge. If I remember right, the pressure must remain above 30 psi thru all rpm ranges.

I bet you will see the pressure fall off when the engine loses it's rpms. Why would it fall off? That will be the next question....

You can get more help over here: www.etecownersgroup.com.

This is a different animal, you need a factory manual, a computer with EvDiags software, and serious study/training to work on these ETecs.
 
Back
Top