P1263 High to Low Side Short - Cylinder 3
P1265 High to Low Side Short - Cylinder 5
P1275 High to Low Side Open - Cylinder 5

Before you condemn the IDM (or even your original IDM) - you need to go exploring and make sure you don't have a bad connection at the UVHC. You'll need to pull the valve cover on the passenger side. Make sure there are no chaffed wires external or internal to the valve cover and that the harness is good and tight. If everything looks good, I would suggest checking resistance from the injector back to the IDM harness. Here's how - GB Remanufacturing - Tech Bulletin #103

I doubt you lost two injectors at once. Much more likely the harness has pulled loose on the front part of the connector.

 

Man thanks for the reply. I will give it a try.

 

I checked the connections on the harness under the valve cover and everything looked good. I traced out the rest of the harness and It looked good. I have 270'000 miles on her. Anyone think injector cleaner will help? I did not have a miss before theIDM went out but the truck does not get driven much and has been sitting for a while? And suggestions now? I appreciate any and all the help.

 

Rough idle

Long story short. Truck died at stop sign for no reason. Changed IDM truck started and runs but idles rough no matter the RPM. At higher RPM's kind of mis fires. New cam sensor, swapped out the injector pressure control, check connections under the valve covers and both are tight. No visible harness problems. I tried to check the wiring harness with an ohm meter but I did not pull any ohms except on two pins that were not listed on the test. Touched pins at IDM. Battery was disconnected and the plugs under VC were connected. Not sure where next to go besides the dealership who's starting price is $750.

 

Either your ohm meter isn't set right, or you've got a short somewhere. That test I linked to should have given you exactly what you need to do to make sure the harness is ok.

 

I would check the wires going over the drivers side valve cover. It's a pretty common problem for them to rub on it causing a short.

 

I agree, check the wires under the air intake hose as these wires lay right on the cover and with high miles would be a real good place for eventual rub that may not even look like much but just a fine line of exposed wire will be a real electrical problem.

 

Ive been helping Juilus with this on and off. We put my idm on there and it still had the miss, so not IDM. His ICP had oil in the connector so we thought that was it, swapped it with mine cleaned connector, same thing. Checked wires on and under valve covers, look good. I'm starting to think fuel or IPR. Kinda acting like mine did when screens were clogged. I think he started pulling the tank last night to check the screens. Just kinda crazy running good, dies, replace module now misses. I don't even wanna think its an injector but I guess thats possible. I guess with two of us having the same truck maybe ought to get a better diagnostic tool.

 

Between the two of you, would be worth buying the AE. I would check fuel pressure. If it is a dirty screen, you should see the fuel pressure jump around. Could also be your IPR solenoid starting to fail. An AE would show if your ICP is fluctuating.

 

I will pull the bed today and check the screens. My thoughts are why would it pull codes, and just pull codes on two cylinders? I seems like all would be missing. Next, I have heard a lot of people say that around 300k the Harnesses under the valve cover all go out and need to be replaced around these miles. Is this true and would you recommend just doing it. they are airly cheap.

 

Neither fuel pressure nor oil pressure would have set the codes you had originally. Those are electrical issues. You could very well have burned pins or loose connections in the valve cover gaskets or UVCH. Replacing them wouldn't hurt anything.

 

Thanks, kind of what I figured. I order the wires and now feel a little better about the $ spent thanks to you. I will let you know in a few days. Any special trick to changing them or is just getting the VC's off the tricky part? How much are those scanners and where do you get them?

 

The only "trick" is the back bolt on each valve cover. 1/4 inch drive with a swivel works. Some guys come in through the wheel well.

AutoEnginuity with the "Total Ford Bundle" (SP03) is $359. You can get it from a number of places. Here is the link from a site sponsor - http://www.dieselsite.com/autoenginuityscantool-pcbased-shipsfromarizonamanufacturer.aspx

 

When checking the wire harness. Do I need to unplug the plug at the valve cover and hook the ground of the ohm meter on each wire being tested with the positive lead of meter connected to the plug for the IDM? OR, just hook the positive lead of the meter into the plug at the IDM and ground the negative meter lead to the frame or battery? The second of the two is what I did and may be the cause of why I did not pull any ohms. Thanks

 

If your checking for continuity through the plug (don't think of it as grounding) put one lead to the end going into the VC and the other lead on the corresponding pin on the end going to the IDM. IIRC, I stuck a needle in the pins on the IDM end.

Sent from AutoGuide.com App

 

Read the test parameters again - GB Remanufacturing - Tech Bulletin #103

Test 1 - measure the resistance between each power feed and each injector’s ground circuit at the IDM harness connector

You basically did test 2 - Measure the resistance between each power feed and ground. This should indicate an open circuit.

 

Testing wire harness with ohm meter

How do you test the wire harness from the IDM to the Valve cover harness? Do you hook the red lead to the plug at the idm and the black to the otherside. I will be changing the harness un the valve covers Friday. Will the old gaskets be ok if they look fine?

 

im not sure if your issue is the same problem i had a few years ago. my truck would be running fine then usualy when i shifted from 1st to 2nd i would loose what felt like 1 or 2 cylinders. if i shut the truck off and restarted it it would be fine for awhile. after about 6months like this it finally wouldnt fix it self anymore.

i took it to a dealership that has a great diesel mechanic. the scan said my IDM was bad, but he tested the harmess between the IDM and the injectors and found 3 wires that were chafed. 2 were touching eachother and one was chafed against the loom. $17 in parts and $300 in labor. he also made a tester to check the IDM to make sure that wasnt the problem. and had the harness and IDm on and off about 6 times. so it was worth the $ for labor.

like i said it mite not be the same issue but mite not hurt to check it out.

 

I changed both the harnesses under the valve covers, triple checked all the wires, only ones I found bad were to the brake, master cylinder. Which need to be replaced. Now I only get one code, P0603? The other two went away but no changes in the way the motor runs. Still misses and pops really bad at 1700 rpms. Injector maybe? I will look at other post but are they fairly easy to change?