1994 6.5L wont stay running ECM code 13

[6.5L_turdburg]

the truck runs fine when it runs usually starts fairly easy as well, but it shuts off randomly while im driving wich to say the least is inconveinent,

the ecm is throwing a code though # 13 wich is engine shutoff solenoid circuit
also the temp gauge on the dash is inoperative it just lays there like a flacid **** no matter how warm the engine is

is the engine coolant temp saftey switch part of the engine shutoff circuit?
how do i know what to test?

i need a wiring diagram for the circuit but have no idea how to get one
haynes repair manuals havent helped much as far as diagrams

 

[6.5L_turdburg]

any help would be aprriciated

 

[Dave Barbieri]

Need a little more info: 'F' or 'S' engine; manual or auto; 3/4T or 1T? I can snail mail you the wiring diagram for your setup, but I'll need to know what I'm looking for.

Dave

 

[6.5L_turdburg]

Need a little more info: 'F' or 'S' engine; manual or auto; 3/4T or 1T? I can snail mail you the wiring diagram for your setup, but I'll need to know what I'm looking for.

Dave

F code C2500

 

[Dave Barbieri]

F code C2500

PM me your address; it'll go out in tomorrow morning's mail.

 

[Dave Barbieri]

Here's a quick 'n dirty test for the gauge and the check gauges lamp driver: pull the connector off the sensor and ground it directly to the head. Your temp gauge needle should swing to 'H'. Your 'Check Gauges' lamp should also light up. No movement on the gauge and no lamp means there's a REAL good chance that your sensor is shot.

You can also test the sensor more accurately using a multimeter/ohmmeter. Here's what you should see at different temps:

105 degrees - 1300 ohms
205 degrees - 220 ohms

Each of the above resistance values are approximate - plus or minus 20 degrees.

Also, check your fuse to make sure it's good.

Hope this helps!

 

[6.5L_turdburg]

ok did that test, gauge pinned and check gauges light lit up, if that means the sensor is good then now what i also tested the other temp sensor for resistance
its seemed good also resistance values changed with temperature changes although i dont think that sensor does anything for the gauge on the dash just the ecm

 

[Dave Barbieri]

ok did that test, gauge pinned and check gauges light lit up, if that means the sensor is good then now what i also tested the other temp sensor for resistance
its seemed good also resistance values changed with temperature changes although i dont think that sensor does anything for the gauge on the dash just the ecm

OK, you're testing the sensor on the front of the DS cylinder head, right? That's the sensor that drives your dash temp gauge.

If you perform the test and everything works, that means the temp sensor is BAD. The test shows you that the circuit is OK, the gauge internals are OK and the Check Gauges driver is OK. 'Nuther words, everyone's doing their job EXCEPT the sensor. Change the sensor and the gauge will start working.

Sorry to sound ignernt, but what temp safety switch are you referring to? I don't know of another temp switch used, except for the charge air temp switch located on the intake manifold.

 

[6.5L_turdburg]

ok do you know where the thermostat housing is? theres a two wire connector conectod to a temp sensor that is mounted into the metal tubing and comes in direct contact with the coolant facing the motor from the front of the truck its slightly to the lefts and infront of the injection pump also if you follow the air line from the stock wastegate its near the bend in that line when it reaches the base of the intake manifold

 

[6.5L_turdburg]

and yes the sensor mounted in the engine block on the left bank in front of the injector is the one i tested and aparently it need to be replaced

 

[6.5L_turdburg]

some vehicles have a engine temp shutoff when the engine exceeds a certain temperature i don't know whether my truck even has that, thats why i was asking , i thought possibly if something in that circuit shorted it might cause a false reading too high and shut off the engine and also throw the code i got. just trying to make sense out a pile of symptoms but im probally inventing problems that wouldnt ever happen

 

[Dave Barbieri]

ok do you know where the thermostat housing is? theres a two wire connector conectod to a temp sensor that is mounted into the metal tubing and comes in direct contact with the coolant facing the motor from the front of the truck its slightly to the lefts and infront of the injection pump also if you follow the air line from the stock wastegate its near the bend in that line when it reaches the base of the intake manifold

You're right - there's a temp sensor in the thermostat crossover. That sensor provides engine temp info to the GP controller at the back of the engine. It tells the controller when the engine is cold enuff to need supplemental heat in the combustion chambers to get started. It prevents your GP's from cycling on when the engine is warm/hot.

some vehicles have a engine temp shutoff when the engine exceeds a certain temperature i don't know whether my truck even has that, thats why i was asking , i thought possibly if something in that circuit shorted it might cause a false reading too high and shut off the engine and also throw the code i got.

Got it. A lot of large cars (over-the-road 18-wheelers) have this type of engine protection circuit. If it's activated, the truck goes into 'derate' - engine output is greatly reduced, the fan is energized, and the PTO drive is disengaged. AFAIK, there's no overtemp circuit on our motors. This is why you hear about guys overheating their engines and blowing headgaskets/cracking heads, etc.

If you disconnect that sensor (the one in the crossover), your GP controller will think the OAT is -20 degrees and go to max heat time. That's a big help if you've had the batteries disconnected. For some reason, the controller doesn't want to cycle the GP's after a power interuption. Dumb. This is your way to override that.

 

[6.5L_turdburg]

You're right - there's a temp sensor in the thermostat crossover. That sensor provides engine temp info to the GP controller at the back of the engine. It tells the controller when the engine is cold enuff to need supplemental heat in the combustion chambers to get started. It prevents your GP's from cycling on when the engine is warm/hot.


Got it. A lot of large cars (over-the-road 18-wheelers) have this type of engine protection circuit. If it's activated, the truck goes into 'derate' - engine output is greatly reduced, the fan is energized, and the PTO drive is disengaged. AFAIK, there's no overtemp circuit on our motors. This is why you hear about guys overheating their engines and blowing headgaskets/cracking heads, etc.

If you disconnect that sensor (the one in the crossover), your GP controller will think the OAT is -20 degrees and go to max heat time. That's a big help if you've had the batteries disconnected. For some reason, the controller doesn't want to cycle the GP's after a power interuption. Dumb. This is your way to override that.

so in other words i have two seperate problems im replacing the temp sensor in the block but im still not sure what the issue is with the engine turning off on its own symptoms point to pmd/fsd failure and my pmd is still in the stock location and i have 219,996mi any advice on how to isolate the pmd as the issue?

 

[Dave Barbieri]

so in other words i have two seperate problems im replacing the temp sensor in the block but im still not sure what the issue is with the engine turning off on its own symptoms point to pmd/fsd failure and my pmd is still in the stock location and i have 219,996mi any advice on how to isolate the pmd as the issue?

Yup. Replacing the sending unit in the cylinder head will cure the limp pointer problem. The fuel solenoid is a separate issue. That's the round thing that sticks out the back of the injection pump. It's computer calibrated when the pump is assembled, so it's not adjustable and not replaceable. There's a little pintle inside there that's driven by an electromagnet. The pintle controls fuel flow thru the injection pump. Gum and corrosion (and sometimes breakage) cause the pintle to behave screwy. This results in all kinds of running weirdness. (surging, sudden acceleration) A quick 'n dirty test for the engine solenoid: start the engine and try to maintain 2,000 rpm. If you can't hold a steady 2 grand your solenoid is going bad. Typically, you'll notice surging, especially with cruise control engaged. The engine will either want to idle or accelerate past redline. Pretty exciting.

However, you mention that the truck runs OK; it just wants to shut down every now and then. That really sounds like the PMD. Do you have a known good PMD that you could swap in? That's the first thing I'd try.

 

[6.5L_turdburg]

no i dont but if the pmd isnt the problem its bound to become one so ive heard so it looks like im getting a heath isolator kit as well
the truck maintains rpms no problem