John Deere 6068M85 Marine Engine Fuel Possible Throttle Sensor Problem

[Art M]

Symptoms:
1. Idle is fine.
2. When throttled, starts fine, then bucks and kicks and blows black smoke.
3. Throttling down takes it back to normal.
4. Also, when cruising, fluctuation in RPMs.
5. Engine load % fluctuates to 100% at times.
6. Computer reads there is a fuel fault (yellow light goes on and off).

I'm leaning with that it's a fuel sensor problem (possibly a wire that got crossed or bad sensor?).

Is the fuel sensor location beneath the throttle arm?

 

[Dslpwr]

Sounds more like suction control valve. What is in stored codes in display. Feel
Free to pm me

 

[Art M]

Bad weather Tuesday I’ll get codes And get back to you thanks for info I’ll try to find location of suction valve. Thanks

 

[Dslpwr]

It’s hidden up underneath exhaust manifold. It’s in a bitch of a location

 

[Art M]

Thanks I’ll scope it out

 

[Art M]

Att-DSLPWR
Fault code SPN91 FMI. 4 throttle signal out of range

 

[Dslpwr]

When are you going to be at your boat? There’s a couple things I want you to check before replacing parts

 

[Art M]

Tomorrow at 1:00pm

 

[andy65]

Following.

 

[Art M]

I have to check wiring .

 

[Art M]

At boat now, if you’re around.

 

[Art M]

Att- DSLPWR Found the problem it had a bad wire connection at the sensor. Cleaned it up and put a wire nut on for now. I’ll take it out for a spin tomorrow to make sure. Then fix it right. Thanks for your help.

 

[Dslpwr]

Was it extended out with a piece of wire? It fairly short lead from the panel

 

[Art M]

It was a short wire 2” not extended. I’ll remember that trick when it gets too short. Thanks

 

[Art M]

Not out of the woods yet!! Engine won’t go above 1670 rpm I backed off Throttle and then gave it again full throttle it only hit 1580 rpm and it stuttered a few times. Fuel looks clean all new filters 1 st and 2 secondary

 

[Dslpwr]

Bring up menu on panel and look for active codes, at that rpm you are on derate

 

[Art M]

No fault light came on and I didn’t notice a code. I was focused on turning the boat around and getting back to the mooring . Before it quit which it didn’t. But my neck hairs were twitching. Today I pulled the three throttle sensor wires back to the dash for replacement. They didn’t look to good. I’m hoping that will do it.

 

[Dslpwr]

Go into menu and open stored codes. That would help a lot. Give me a call at my shop, 207.483.2382 I’ll be out on service call this am but will be back after lunch

 

[Art M]

I should be able to get the codes tomorrow didn’t make it to the boat today.

 

[Art M]

Store codes: SPN 3511. FMI. 4. Sensor supply 3. Voltage out of range