I need HELP!

Okay I changed out the key switch harness with one I had out of a wrecked truck here at the shop. 2 of the prongs on the original one were burnt slightly. Put new one on and no change does the exact same thing.

So I changed out the fuse block with one here at the shop and still no change.

I don't exactly know where to go with it at this point.
 
Sounds like a bad ground. Do a ohms test on the wires check the plugs to the ECM
"WIGGLE TEST" Your losing voltage to the ECM when cranking figure out why and it will start! You May also have a bad PCM!!
 
syrupdawg said:
Okay I changed out the key switch harness with one I had out of a wrecked truck here at the shop. 2 of the prongs on the original one were burnt slightly. Put new one on and no change does the exact same thing.

So I changed out the fuse block with one here at the shop and still no change.

I don't exactly know where to go with it at this point.
Click to expand...

Well crap!
 
I put a test light on the injector while cranking and it barely lights the test light. It just barely does flicker? The ecm is not firing the injectors for some reason. Whether its the power supply to the ECM or the ECM to the injectors. How can I test that? What wire supplies power to the ECM?
 
Your going to have to pull up a wiring schematic for that to hard to explain but double check your battery connections + and -!! and do the resistance test on all the battery wires! I've seen bad main cables do that. Also test light not a good idea can cause problems. Use a multi meter
 
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dangerous06 said:
Your going to have to pull up a wiring schematic for that to hard to explain but double check your battery connections + and -!! and do the resistance test on all the battery wires! I've seen bad main cables do that. Also test light not a good idea can cause problems. Use a multi meter
Click to expand...

Resistance test on the cables?
 
The oil pressure sensor is just a switch.
On a properly working truck, you can unplug it with the engine running and jump the terminals with a paper clip. Jump in the cab and rev the engine- the oil pressure will fluctuate w/ rpm. The gauge is a dummy.
 
dangerous06 said:
Sounds like a bad ground. Do a ohms test on the wires check the plugs to the ECM
"WIGGLE TEST" Your losing voltage to the ECM when cranking figure out why and it will start! You May also have a bad PCM!!
Click to expand...

agreed. when he is cranking on it the starter is robbing all the amperage and i bet the ECM is getting less than 10 volts.

i had a bad set of batteries that i would have bet money were fine and i had some dash/ starting issues going on. i hooked up my 2nd gen to my 3rd gen with jumper cables. left the 2nd gen running for 10 mins and the problems went away. i went back to orielleys and load tested both batteries myself. load tester showed to be good batteries. bought 2 brand new batteries and it never happened again.

amperage is everything with a modern day diesel. too many sensors and computers to keep alive while turning a motor over!
 
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