Being that im a 3rd gen guy, this is my first post in the 2nd gen forum. I have a customer at work that has a 1995 3500 cummins of course that keeps shutting off. I have driven this truck when it did it and it just acts like you cut the key off. You can cycle the key switch and it fires right back up and may run another hundred miles and not do it again. I know a few things to suspect, but wanted to know if any of you have already encountered this and what your opinions are?

The engine has a P pump and is pretty much a cummins. Nothing added and nothing removed. It has an auto trans.

Thanks for any help guys.

 

I do believe the ignition switch and harness had a recall due to excessive heat and melting. I also think the headlight switch and harness had a recall for the same problem. My truck quit running after the smoke left the steering column. That is all I can think of. Maybe you could also check the electrical connection at the fuel cut off solenoid.

My.02 cents

 

next time it does it don't turn the key off just pull over and look at the fuel shutdown selinoid and see if its in the up position. If it is not then thats probably your problem. When the key is turned in the run position the selinoid raises up allowing fuel to flow key off the selinoid goes down stoping the fuel flow.

 

The selonoid is possible, however the first failure mode of these is hard-starting of the engine. Eventually, it will not shut off, and your selonoid is failed. I suppose it could electrically malfunction and activate when it's not intended to, which sounds a lot like what's happening.

Take it to a local dealer and ask to have all the recalls checked and corrected. There should be cruise-control, throttle-cable, and ignition-switch in addition to a fan switch on the dash. Also the hood latch has a recall on it too. All simple for a delaer to correct, and free to you.

 

Do not replace the shutdown solenoid, it's probably the most needlessly replaced item on a 12 valve, expensive too.
The solenoid is a heavy duty unit that will easily last the life of the engine, the problem most always lies with the relay that activates the solenoid or the wire from the battery that feeds it. These are on the pull up circuit though.

From your description it's the hold circuit that is failing, I would suspect the key switch or the wiring in the steering column. Key switch for a '95 is around $30 at Napa. After removing the column cover tilt the wheel up and down and see if any wires are loose.

 

Alright guys. Heres the deal. I got the truck backa and found the blue and orange wires at the battery on the drivers side were coroded and the wires broke when I took them off. I corrected that issue and test drove the truck. It seemed to do fine. It sat over the weekend and whnen I came in today I went to crank it and it would not. It only runs if you hold the key in the start position. I have three pins at the solenoid connector. One is hot with 12 volts when the key is in the on position and the middle pin is hot when the key is in the run position. I can supply 12 volts to the pin that is hot in the on position on the solenoid side and nothing happens, I can supply 12 volts to the pin that gets hot when the key is in the crank position and the solenoid kicks out to allow fuel flow. What is going on here guys??? Its killing me.

Thanks for all the info so far.

 

The key on position solenoid coil isn't enough to lift the plunger.
The solenoid takes a lot of juice, even though you are measuring 12 volts you may not be getting enough amps to lift or hold due to a bad connection.
Sort of like a kinked water hose, water comes out but volume is reduced.
Look for bad connections, corroded wires.

 

I just went out and jumped the center pin which gets 12 volts when the key is in the start position, and then moved it over to the other pin that is hot when the key is on. the solenoid then held itself correctly. I assume from that test that this solenoid has crank and a hold position and my hold position was not working. the hold position does not reauire the amperage that the crank position does. After performing this test, the truck cranked like normal so I am onder the impression that the solenoid is going bad. The rubber boot is torn and no longer sealing and theres no telling how long its been this way. The engine is fairly clean so I know that they wash it regular. I belive I will call Cummins Midsouth and get a solenoid ordered for it. Where is the relay that activates this solenoid located? I would like to test it out but I cant find one that makes the solenoid loose power?

Thanks again guys.

 

HOLY COW, $307.68 from Cummins. Does anyone have another source for these bad boys????????
Im gonna call dodge and see but they should be higher? No?

 

http://www.fostertruck.com/dodge/

 

There is nothing wrong with your solenoid, it's full of crap from not having a boot, take it off and clean it.
No such thing as weak solenoid, they either work or they don't.

 

Thanks for all the help guys. The plunger and solenoid itself did have some rust colored dust all over it but I think it was an electrical issue inside the windings. Any way, it now works like a real truck with red **** mounted on the lower part of the dash that says ENGINE STOP. Thats right, for $48 I put a manual stop cable on it and all is well. No more is it gonna die on me or is it gonna start for me. It is either on or off now. Thanks for the help everyone.

Patrick.