2001 evinrude 4 stroke wont run over 2900 rpms

[ignorant]

this is a resurrection of an old post from 2013...
I have the same Evinrude with the same issue. model E50PL4SI, serial # 18008304

Idles fine but when RPM reach 2900 it begins surging and will not go above that point.
I am in the process of trying to buy a service manual as suggested., but have not found one yet.
I have worked on lots of equipment, but 4 stroke boat motors are completely foreign to me. I will do my best to follow any instructions and report results, but please be patient and understand you are not talking to someone with experience.
The previous post indicated the problem could very well be temperature related, but not sure how to trouble shoot.
My motor has no "tailtell" water discharge. There is a rubber plug in the rear and if I remove it water will flow out but it is like an old man at the urinal, not the strong stream that young men and normal motors have. Should that plug be left in or should it be out?

Any suggestions?

any and all help will be appreciated.

 

[racerone]

Find the neutral switch on the motor linkages.----If that switch is stuck the computer might think the motor is in neutral still.----Then it will not rev up.

 

[ignorant]

thanks for the repsonse. I am looking at parts diagrams to help me identify it. all those parts crammed in a small space ! will try that tomorrow afternoon. Tied up with grandkids tonight and in the morning

 

[ignorant]

thanks for the repsonse. I am looking at parts diagrams to help me identify it. all those parts crammed in a small space ! will try that tomorrow afternoon. Tied up with grandkids tonight and in the morning

Best I can tell the neutral switch is working ok. At least it is being opened and closed at right times. Just visual no electrical testing. I and still bothered by two things… possibly related?
No water discharge- is that by design?
Also bulb in fuel line never really firms up good… possibly just starving for fuel?

Plan to work on fuel bulb issue tomorrow and see if I can eliminate that variable.
Still open to all sughestions
Thanks

 

[Crosbyman]

get the watre flowing check engine temps !! several sensors can keep you in SLOW mode

 

[ignorant]

get the watre flowing check engine temps !! several sensors can keep you in SLOW mode
View attachment 383318

Crosbyman, thank you for reply. This morning I think I was able to eliminate the fuel bulb as the issue. The paragraph you highlighted about ECU kicking in if motor starts at too high RPM has my attention. I start my motor giving it near full throttle and it surges until I bring it back to idle. Would the ECU not “reset” once the motor is at proper idle speed?

Do you happen to have a link to the manual you used in your post? Would like to study the diagrams it references. I have a hard time identifying what’s what and pictures help
Thanks

 

[Crosbyman]

check your PM in a few minutes go to the small enveloppe top right to find personnal messages

 

[Crosbyman]

not to familiar with pre ETEC versions ...try searching UTUBES.
some JOhnson were Suzuki made ...

 

[racerone]

It is a SUZUKI built machine.

 

[Crosbyman]

see link on SUZUKI fault codes

Suzuki Outboard Fault Code List [DTC Chart] |

How do you pull fault codes on a Suzuki outboard? How do you reset the check engine light on a Suzuki outboard? What are the official Suzuki outboard DTC codes? Get all the answers!

powersportsguide.com

 

[ignorant]

see link on SUZUKI fault codes

Suzuki Outboard Fault Code List [DTC Chart] |

How do you pull fault codes on a Suzuki outboard? How do you reset the check engine light on a Suzuki outboard? What are the official Suzuki outboard DTC codes? Get all the answers!

powersportsguide.com

Attaching a couple pictures and video.
If I read the light correctly it is flashing a 23 code when I fist turn in key. Did this before I even tried to start.
The Suzuki code reference indicates this will put motor in safe mode the evinrude manual say does not put in SLOW.
If I read correctly this is an air temp sensor and code means either air too hot or could mean no signal from sensor. Since motor was cold I am leaning towards no signal

Does that make sense?
Trying to ding a picture so I can identify it in my motor.
View attachment IMG_2655.MOV

 

[Crosbyman]

suggestions only... up to you to decide ! before... proceeding test your wiring ECU TO IAT for loose connections frayed wires broken wires

sensors are frequently a variable resistor that fluctuates according to conditions or position (ex: TPS) or... simple on-off devices that are triggered from one state to the other (open to closed or closed to open)

not knowing which is which for your temp sensor I would say open the connection (ex single wire device) or short the connection if 2 wires or ground the wire ...all depends on what the ECU logic is waiting for.



see how the start process changes or not.

Slow mode seems to be 3000 rpm whereas SAFE on a ETEC is around 1200

 

[Crosbyman]

see typical/similar sensor test of an IAT on a suzuki car

Careful.... ...author talks voltages when his meter is actually on the resistance scale near the hot water test. the hot water test just varies the resitor values as it gets hot.

IAT drops to a few ohms when HOT and max resistance when cold.

on ETECs..... sensors are also fed 5v like in this video with key ON only

so you can check that 5v to....

if the ECU does not sense the IAT at KEY ON... due to open wiring it will declare a code.

this is more indicative of loose wires loose connector oxydized connections etc... to check the wiring closely !


good luck troubleshooting.. it is all I can do from here

 

[ignorant]

suggestions only... up to you to decide ! before... proceeding test your wiring ECU TO IAT for loose connections frayed wires broken wires

sensors are frequently a variable resistor that fluctuates according to conditions or position (ex: TPS) or... simple on-off devices that are triggered from one state to the other (open to closed or closed to open)

not knowing which is which for your temp sensor I would say open the connection (ex single wire device) or short the connection if 2 wires or ground the wire ...all depends on what the ECU logic is waiting for.
View attachment 383346


see how the start process changes or not.

Slow mode seems to be 3000 rpm whereas SAFE on a ETEC is around 1200

Pulled the IAT still got code. Jumpered the contact and still got code.
Something has changed though.
With ears on I can put the motor in gear and go to over 3000rpm with no surging.
But… after a short time the HOT light come on.
Never tried to run a motor at those high rpm with just ears. Is that normal?
May be as simple as needing new water pump impeller ? Normally I would look for a strong water discharge. This motor has no water discharge. It has a plug with oring about 3/8 diameter in rear. If you pull that plug water will come out but very weak. I can’t seem to find any reference to that anywhere in my searches

 

[ignorant]

Pulled the IAT still got code. Jumpered the contact and still got code.
Something has changed though.
With ears on I can put the motor in gear and go to over 3000rpm with no surging.
But… after a short time the HOT light come on.
Never tried to run a motor at those high rpm with just ears. Is that normal?
May be as simple as needing new water pump impeller ? Normally I would look for a strong water discharge. This motor has no water discharge. It has a plug with oring about 3/8 diameter in rear. If you pull that plug water will come out but very weak. I can’t seem to find any reference to that anywhere in my searches

Ok in the manual I found that it has “flushing” plug. So that is what I am seeing. At it does not have telltail like other motors.

 

[ignorant]

Ok in the manual I found that it has “flushing” plug. So that is what I am seeing. At it does not have telltail like other motors. View attachment 383351

I am claiming victory but will not have a chance to go to lake for a couple days to “test”
Still gettin code… will check wiring more and possibly order new IAT sensor, by it does not appear to be causing the SLOW mode.
Overheat went away when I repositioned the ears so the matched the intakes better. And with motor in gear I can run 4000 rpm with no surging.
My opinion of what happened/caused the problem…
Boat had been sitting for almost two years.
I would not idle. I adjusted throttle linkage to make it idle faster.. in doing so I think I created the issue with the neutral switch.
Running fresh gas with sea foam evidently cleaned up the idle issue and the motor was actually idling too fast and still causing neutral switch issue. I adjusted linkage to a point where it was idling correct but evidently not enough to fix problem I caused on neutral switch. I adjust linkage another 1/2 turn and neutral switch issue resolved.

A trip to lake will be real test, but I think I may have it going.

Really appreciate all the help and suggestions. I have learned a lot.
Thank you!

 

[Crosbyman]

Never.. never run 3-4000 rpms on mufs !! or hose !!

 

[ignorant]

Never.. never run 3-4000 rpms on mufs !! or hose !!

Will put that in my tool bag. Did not realize it could cause issues. Will not make that mistake again. Thank you for all your help.
Going to try to get it in the water Thursday evening after work. I live in central Texas area and our local lake is terribly low. It is like a mine field getting off boat ramp. If you can dodge obstacles for about 100 yards you can hit the channel and open up.
I will give a report … fingers crossed!

 

[Crosbyman]

my son (Canadian) was in Austin last week... to hot for him and...me !!

 

[ignorant]

my son (Canadian) was in Austin last week... to hot for him and...me !!

I’m About 60 miles north of Austin. Been brutal hot this year even for those of us who have lives here all our lives.