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Discussion Starter · #1 ·
Guys,

Could really use some help here. I'll get right to it.

- Drove truck other day "Check Engine Light" came on starting running like **** and sputtering. Took it back home.

- Ran diagnostics test on it, no codes but my chip (which is always ignored) no problems with chip.

- Took the IDM off and ran resistor test from the IDM harness to the UVCH on both banks. Bank 1 (Driver side) all 4 injectors running at 3 OHMS which is good.

- Ran test of Passenger side, not even reading anything on multimeter. All 4 injectors no reading

- Took off valve cover, took the UVCH off ran tests on it

- With UVCH connected to solenoids on injectors (3 Ohms), UVCH off and tested by itself (.5 - .7 OHMS)

- Kind of stumped right now. Is it the harness going to the IDM from the valve cover? Are these correct OHM reading?

- Continuity test on the harness passed on all 4 injectors with it off my truck

Please help, don't know where to go from here
 

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Not sure how you are tested them.
Whith the harness disconnected. The injector pins are the third back from front thru to the third to last on back end. I use a repair pigtail plugged into at UVH so I can more easily test.
Center pin is common for the injectors.
Harness readings unplugged and tested from end of each wire to each end, yes .5 is great
 

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Discussion Starter · #3 ·
I took the harness off and used my multimeter.

The 2 pins on both left side and right side on the end are the Glow Plugs, so the 5 in the middle are the injectors, common being the center of the 5.

With my mulitimeter, on OHM settings. I probed the inside black (on harness) and touched the center pin on the (outside of the harness, the plug middle pin) giving me a (.7) OHM reading on all 4 injector harness ends.


When I install the harness back into the truck and hook up the harness to the 4 injectors. I am getting (3 OHMs on all 4 injectors), testing from the plug on the outside of the valve cover.

I guess my question is, what are the proper OHMs from doing certain tests, so I can diagnose what's going wrong:

- OHM # from IDM - My truck 3 OHMS on Bank 1, no reading on Bank 2

- OHM # from Valve plug (outside) - 3 OHMS on Bank 1, didn't test Bank 2

- OHM # UVC Harness itself - .5 - .7 OHMS on Bank 1, didn't take off the Bank 2 valve cover yet
 

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Discussion Starter · #4 ·
Sorry, I didn't see you said .5 was great at the end of your comment.

So what could be wrong?

My only guess is the harness going from the IDM to the Valve Cover? Since it won't give me a reading when I probe at the IDM?
 

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I'm sorry buddy long week. Left for Ocean to leave upon arrival due to storm. Then came back to work. So I'm kinda not following your procedure, due in part to my inability to visualize your process, due to burn out. So.....

So, I have a set routine. Some peoples routine's vary.

When I have an issue like missing ACCOMPIED with codes, I; first disconnect UVCH. I then attach a engine harness to UVCH. I then attach to to UVCH with this is engine harness repair.
I ohm the first two pins which are glow plugs. I do this by with probe to glowplug wire and clean spot on block NOT battery. These are the (2) front and back pins. I do the glow plugs because why would I not want to know and answer a customer. It also can show an issue with the gasket pins. I look for .2-2.0 for good plugs per Beru. Ford may be at .3 in different year manuals but a diesel tech that sees Berus in other machines, their manuals and have spoken with Beru, .2 is good. Keep in mind ohm readings will vary with actual temperature of the glowplug itself. Per Beru, any bridges ( which we do not have ) should be and plugs be tested individually, perferrably at or near to 60-70 degrees faraheight. Engineers gettin all crazy on temp but... it will swing. His summer a dealer tech here was on this issue somehow questioning this. Went out to give degree shop. Posted pic hooked up on floor just brought in inside. As it warmed on tile in photo in front if wood burning stove you could see it change.. Splitting hairs... That stuff. Don't worry about it.

I the go to common pin, the center pin for injectors. I look for 3.0-3.2. I know I'm gold there but you may see little higher but you won't see lower despite what you might read from posts you might read and if so that coil was out not long from that reading and subsequent posting.
If anything reading are off, I pull the cover and look for disconnected or partially connect UVCH. I look for burnt or grown pins in the engine harness by popping the blue plastic pin locker off. Regardless of findings of inspection there, I clean with electrical cleaner and pack pins with dielectric grease and reinstall blue pin locker in the engine harness side.
I then ohm from test rig ( repair pigtail, engine harness side ) to the inside pins if the gasket to chech the integrity there.


From here, I go backwards from UVCH engine harness connector. I ohm each wire by probing end terminals with connectors Dissconnected. I look for right about .5 ohms.

Electrical problems in this area almost always create codes.

Missing can be from stiction in the injectors (7.3s usually see it around 1500rpm range), broken rockers ( very common from D.IY and less knowledgable pros from hydro locking the cylinders after injectors in the 7.3), less common valve guides worn out.


Missing can be low oil cutting injectors in and out.
Good luck you will get it with help from all the guys here.
 

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