CM870 code 259 Fuel shutoff solenoid

[tlzimmerman]

Completed the EGR tune up on my CM870, didn't replace any sensors (yet) but did clean them all.....still don't think the truck has as much power as it should after the exhaust leak issue and EGR hooked back up ETC. I have no Check engine light, but the odometer shows 2 faults. Used the diagnostics switch to flash out the code....it flashes 259. Looked that up and that is the fuel shutoff valve. Doing some reading on the internet and what I am seeing is this code happens when the ECM commands the fuel switch closed, and it doesn't drop pressure as anticipated. Some are also saying it comes with a torque de-rate. Now, interestingly enough since I have owned the truck when you turn the key off it does NOT shut the engine off immediately. It takes 4 seconds, and then the truck dies. It never spits or sputters, so I thought it just took that long at key off until the ECM turned off the fuel solenoid. Is that normal or does this sound like related issues? Replacing that solenoid would be simple enough, is that my first step? Also this truck had the stupid PukeDits fuel pressure harness on it with a rheostat. I removed that and restored the OEM wiring. I don't think this should have caused the code and issues, but thought I would throw it out there.

2nd question according to the light flash procedure I have I SHOULD be seeing the CEL flash before the stop engine light to show a new code. The CEL never comes on...does this mean I have a light out or the idiots before me disconnected it? Can that even be done? I haven't had that part of the dash apart yet.

I am starting to yearn for having insite.....should probably just bite the bullet and get it.

[Nilao]

CEL should come on when you turn the key on during the dash self test. If it's not then the led/bulb is burned out.

[Rawze]

About 3 years ago, I had a friend who came over here who's engine ran for about a year where it would stumble for several seconds after shutting off the keyswitch. Then all of the sudden one day, it ran for almost 2 minutes after shutting off the key in the dash. Turns out the fuel shutoff solenoid was sticking and going bad. Replacing it though, only solved the problem of staying on for a couple minutes. It still stumbled/ran for several seconds when shut off even with the new one. It was not until he replaced the metering actuators, that the whole problem got solved.

I also had one guy come here who's engine would rev up a few rpm at idle randomly, and would also hesitate several seconds when shutting down. I watched his commanded fuel flow in the ECM and it was commanding zero fueling when it would do this. His was a bad metering actuator as well.


=-=

I don't know about the CM870, but my CM871 (same IFSM module) shut off in the middle of the interstate, no warning whatsoever about 3:00 A.M. for a similar code. The fuel shutoff solenoid died. I gutted, then re-installed the outer shell and gasket so that I could get the truck home to fix it properly.

The truck ran perfectly fine without the guts in it, and the engine did not have any hesitation shutting off at all. I was fully expecting to have to unplug the ECM to get it shut off once I got it home, but was surprised find that it shut off just fine. -- It has now been like that for more than a year, I decided not to replace it so that it does not put me on the side of the road again. Truck runs fine with the fuel shutoff solenoid gutted and shuts down right away when the key-switch is turned off.

- It is just speculation, but this leads me to believe that since my own truck has zero hesitation in shutting off without the shutoff valve in place,.. a leaky fuel actuator would definitely cause one to stumble and have issues like not shutting off for several seconds. This would likely be true even if the shutoff solenoid was working until fuel pressure fell off to the point that it could no longer feed the cylinders.

-- So in your situation,... A sign of worn out/leaky actuators perhaps?? Who knows. If one is worn out, they all likely are if they are the same age. Not saying that your power and other issues are the actuators, but it is something to think about.

[tlzimmerman]

The funny thing is though....there is no stumbling at all. It runs perfect as if the key is on for 4 seconds after it's off....and then turns off perfectly. It's why I didn't question it before. I think I'll order a shut off valve and start there. Actuators are probably next.

[tlzimmerman]

Just priced actuators.....holy crap higher than I expected. Here is hoping it's the shutoff solenoid!

[Rawze]

(08-21-2017 )tlzimmerman Wrote:  Just priced actuators.....holy crap higher than I expected. Here is hoping it's the shutoff solenoid!

last time I priced them they were about $600 ea.

[tlzimmerman]

Yeah that is what I was finding, $640 each. Cutoff solenoid will be here Friday or Monday.

I can pull the wire to the solenoid while the engine is running and it doesn't turn off....so its bad either way. Code 259 throws a derate either way according to a few sources I have found....so new one is getting put on. While I have that off I am going to pull and clean the actuators and reinstall, seems like everyone who takes them off knocks crud out of them. Shouldn't hurt anything. Thanks for telling me more about them whether that ends up being the problem or not....on the list of "future schtuff to replace" now.

CODE REASON EFFECT
Fault Code: 259
PID: S017
SPN: 632
FMI: 7/7
LAMP: Yellow
SRT:
The ECM detected that the fuel shutoff valve is stuck open mechanically or leaking.
Engine will have a torque derate.

[Brewster64]

I had same issues on my 871. Causes silent derate. It will keep derating til you change fuel shut off selenoid.( 70 bucks) make sure you clean up the little block and piston it's mounted on, as this can cause it to stick. Carb cleaner and Emery cloth works great. Easy fix.

[tlzimmerman]

Replaced the solenoid today.....same difference as before. Went ahead and took all the pieces of the valve apart.....pretty sure I am missing a spring! I couldn't figure out what held it closed when power was off from the solenoid.....so I pulled up quickserve Best guess the solenoid failed and wouldn't allow the motor to run (Like Rawze) so they took out the spring and never replaced it....so now I have the code.

Anyone want to chime in that has had it apart. According to quickserve there should be part 129768 in there "Valve Spring", 5 pieces, and I only have 4. Going to see if the local dealer has one in stock before I order online.