Fuel solenoid randomly losing 12v

94 international 9400. cummins n14

Truck randomly shut off while driving. picked and probed at it all day. sometimes it starts normal and runs 30 min then shuts off, sometimes runs a few min, sometimes won't start at all. every time it shuts off or won't start, the fuel shut off solenoid does not have 12v. what would cause this?

we've pretty much ruled out a broken wire. the ecm is getting power. ecm fuses are good. ecm was also rebuilt last year..even tried a backup ecm and it still had same problem. could a faulty sensor cause this?

tomorrow I will be splicing in a new style data link connector so we can get a scanner on it

 

so here's the update. went out there today so I can rewire a newer updated data link plug for the mechanics scanner. while we were focused on the active codes, 422, and 433....I noticed the solenoid was getting 12v ALL day but still would not start. but, we were focused on maybe a sensor causing the no start. long story short, fed 12v to the fuel solenoid via probe, no click! put a spare fuel solenoid, probed 12v, click! so I'm guessing the solenoid was going out, causing random run time lengths until it completely went out...which was why no start all day today until replaced.

what i don't understand, is why would the 12v wire randomly lose 12v yesterday. mechanic said hes thinking maybe the internals of the solenoid were causing the ecm to trip the 12v...but I don't know. any of this make sense to anyone?

ran the truck for an hour no problem, drove it home no problem. started it up after sitting a few hours, no problem. still have codes 422 and 433 but I'll worry about that later

 

I've had 422 on for years now, already replaced the sensor a few years back and it still comes on, thinking it's a wiring problem. 433 is new though, although from what I've read it should cause loss of power but no engine shut down. supposed to run my truck today so I'll see what happens!

 

i did forget to ask, would a failing fuel solenoid cause the wire to lose 12v? I figured the solenoid just doesn't click anymore when it goes out.

ran all day with no problems, so I'm hoping that's all it was

 

what's weird is we swapped to a spare ecm the mechanic had, and it it did show a fuel solenoid code, but then when we swapped back to mine it wasn't there..it was odd.

ran all day friday too with no issues