Engine/Transmission (1994 - 1998) The problems just keep coming. . .

[78cummins-wagon]

asside from not having any overdrive (which i still cant figure out ) the truck does not start. it cranks over starts for a few seconds, then immediatly dies. one of the three wires (the three that go to the transmission, 1 being pin 54 from the pcm; for locking and unlocking the torque converter) shorted out and that leades me to where i am now... any ideas?? everything else seems to be working fine. thanks alot...

 

[Missouri Mule]

Sounds like your fuel shut off solenoid hold up coil is not working. Turn key to run position push fuel shut off solenoid rod up and see if it stays.



The only other thing I can think of is that your idle mite be way low.



PCM has nothing to do with running engine with a p7100 injection pump!

 

[78cummins-wagon]

will the truck run with out the crank position sensor? when i start it it will fun for a few a brief moment and then just shut down. all of the gauges seem to work, with the exceprion of the tach. it does not move at all. if i disconnect the shut off selonoid it will just crank over no start what so ever. any more ideas?

 

[78cummins-wagon]

held shut off selonoid in the up position and the truck started, but had no tach. any ideas??

 

[RLaJeunesse]

Check your ignition run fuse in fuse box left door panel.

 

[BigPapa]

The engine will run without the crank position sensor but you will have no tach and the alternator will not charge.



Back to the solenoid, it has TWO coils, one PULLS it up when you turn the key to the START position and one HOLDS it up when the key is in the ON position. If the engine starts at all then I'd say the PULL-UP function is working. Try what Missouri Mule said, turn the key to the ON position, go around and pull the lever attached to the solenoid up and see if it stays there. If the HOLD-UP function is not working the spring in the solenoid will push the lever back down.



If that's working properly, I'd say it's the neutral switch or that you still have a momentary short that's killing the solenoid or the neutral switch. There's just nothing else ELECTRICAL there to keep it from running.



Good Luck,



Scott

 

[Dave M]

It sounds like you have 2 problems... 1. the engine won't keep running and 2. you have no tach. As was said before, the crank senser is not needed to keep the engine running (true on my 97 12V but 24V trucks this is not true... . thank yourself for having a 12V... . Yeeeeesssss!) but the tach gets its signal only if the crank sensor is working.



Try having someone pull up (or tie wrap it up) the fuel solenoid while you crank and keep holding it up to see if truck stays running. If it runs and when you release the solenoid it dies then the "Hold Coil" in the solenoid is bad... ie... you need a new solenoid. Before replacing the solenoid I would first try to remove the solenoid and clean the bore and plunger with brake cleaner and then use silicone spray (not WD-40) to lube it. This worked for me when mine would fail to start... . a little different then your problem.



I also experienced a bad crank sensor and the following things on my 97 were effected (but the engine would run)... . not sure if newer trucks need the sensor to stay running:

1. No tach

2. No speedometer

3. No alt charging

4. No AC but fan worked and all turn sigs and lights



The gage check (key on turns gage lights on) light that did not light are:

1. Water in fuel

2. MIL

3. GEN

4. Airbag



The following lights worked:

1. ABS light

2. oil pressure light

3. seatbelt light, Brake light, blinker arrows, headlight indicator lights.



You could still have a bad CPS (Crank Position Sensor) or sometimes called an ESS (Engine Speed Sensor). You can get one from Cummins or I got mine from NAPA for about $75.



Here is my thread on my failed CPS:

https://www.turbodieselregister.com...ons/184945-electrical-woes-maybe-bad-pcm.html



Dave

 

[78cummins-wagon]

got it fixed. corroded wire melted the rest of the way instead of the fuse. no big deal, nothing a little shrink wrap and some solder couldnt fix...

 

[Dave M]

got it fixed. corroded wire melted the rest of the way instead of the fuse. no big deal, nothing a little shrink wrap and some solder couldnt fix...

What wire?

 

[78cummins-wagon]

not sure, but i think it was the fused positave wire someing from the fuse pannle

 

[robbiesworld]

my 95 did the same thing. The positive wire going to the fuel shutoff relay fell/broke/rattled off the battery terminal