It should still start with only one pigtail bad.

 

You either have to Get the code read , Ohm the injector wiring , or pull the cover & look at the wiring ...

A bad wire can shut down one side of the motor . If the other side is not up to it , it won't start ...

 

On each pigtail there are 5 wires. Which ones are for the injectors. Which wires do I short together to get the ohm reading.

 

The outermost pins (pins 1 & 5) are for the glowplugs. They should not have continuity with each other or the center three. The center three are for two of the injectors in each bank. The ohm reading between each outermost injector(pins 2 & 4) and the center pin (pin 3) should be about 3.2 ohms (if I remember correctly). Pins 2 & 4 should also not have continuity with each other.

 

Ohms look good on the injectors, although I found another pigtail where it burned on the end, but those injectors checked out okay with a 4 ohm reading. I bet that glowplug is gone. Oh well, I will just clip that wire when I get a new pigtail.
I took apart the IDM and with KOEO, I tried to find a 48 volt reading. None detected. The only voltage going into the IDM was 4 12 volt pins, but I tried getting a voltage reading off the nut inside the IDM and it was only 12 volts. Is that my problem?

 

A friend of mine brought over a scanner from Snap ON (blue point), and when he first plugged it in, it said "No codes". Then the scanner said "No communication". He also tried a different scanner on it a few weeks ago and it acted weird. Could it be my PCM?

 

I've read on here lots of problems with scanners. I'm guessing your PCM is OK.

 

it would be nice if u know someone else who has a idm you could swap and try to see for sure.I replaced a bad idm recently and for awhile symptoms appeared to be a bad pcm.

 

Between the HPOP and the Fuel filter there is a small pigtail with a very small looking relay or something on it. What is that for? The little relay thing is only about an inch square.

 

Its the water in fuel PCB, is a little amplifier / switch that connects to the actual water in fuel sensor on the filter canister. It is the device that turns on the water in fuel light in the cab. Get water in it and you will get false reading. Happens when power washing engine was done.

 

New information: Help! Help!

With Key off I checked the continuity of the 2 prong IPR harness. It has greater than 20,000 ohms of resistance. Is that right?

With Key on I also checked the voltage on the Voltage leg of the ICP and it is 5 volts. I thought I read somewhere it should be only 1/10 of that.

 

What does the vacuum line coming out of HPOP and going to the bottom of the fuel pump do? Mine is totally disconnected.

I did find continuity going from the IPR 2 prong harness to 2 different pins on the other end (5 pin harnesss)

 

There is no line from the HPOP to the fuel pump. could you be looking at a line that goed to the bottom frontof the fuel bowl on the passs side if so thats the drain line for the fuel bowl

 

would it be the line on the right with the hose clamp (drain line)

 

I think that is it. It comes out of the bottom of the fuel pump. Looked like it went to HPOP. It is all hard and brittle. Guess it is no big deal.