I'm suppose to be getting my IDM today. Overnighted from Florida. Local Ford Dealer here had one in stock for just $750. I purchased one for $349.

I know my PCM was bad because, I shorted it out pulling a chip from it without disconnecting the batteries. Immediately took a dump. I think it just lost its memory. The Engine Light and Wait to Start Light never went off with the key on, when normally they would and it would not start. The only thing I know about these Diesels is what I've learned through this experience. I have done alot of Research recently. I've talked to several people that said the IDM goes out 100 to 1 compared to the PCM. When your cranking the engine, the IDM should be putting out 115VDC to the injectors or it ain't gonna start. Also the injectors use Oil Pressure to Operate. That's what the High Pressure Oil Pump is for. If the IPR is bad, it won't start, (controls Oil Pressure to the Injectors). The CMP is probably the most common part that goes out, that prevents starting. You really need a good scanner, then you could see what all of these sensors are actually doing. If you unplug the ICP Sensor, the PCM will take over and it should start if that part is bad. You need to check the Fuel Pressure at the Right Head, Left Head. I'll let you know, My IDM should be here anytime, but it will be late when I get back today.

 

Did anyone check the oil res before cranking? Oil can drain back and cause a hard start until the lopop gets primed up.We finally fig that out on Rpquetts truck. Also, disconnect the idm and use the harness and pull a ohm resistance test. It should be under 4ohm. This checks all connections from idm to the injector. This tests the injector harness, uvc harness and engine harness all in one shot. I dont know how to pull the wiring harness color codes off of my cd or screen capture to post.

 

Oil level in hpop is correct. I pulled the connector from the icp and it made no difference. About the ohm test, where is the idm located? I know where the pcm is. If I pull the connector from the idm, do I ohm each wire to ground or to another wire? I assume this reads resistance from the connector plug all the way through to the incectors.

 

1. Check IDM relay in BJB make sure it is good....As kwikk said no power to IDM no power out

Once sure Idm is getting power remove driverside wheel well and look up to the right.

Attached is wiring diagram from IDM to injectors

 

Thanks amiller93 for the schematics. The service manual I picked up from the local auto parts store doesn't have a schematic for the idm or the pcm. I'm not sure which relay feeds the idm but I pulled all the relays from the black box above the fender well and bench tested them. I applied 12 volts to the coils and each one pulled in and out. I ohmed through the contacts and all seem to be ok.
Do you have a schematic that shows the power coming in to the idm? If I can verify power is going in, I can then test for voltage coming out to the injectors. Thanks again.

 

here ya go

 

NEW IDM, Still, NO START, Looks like I'm gonna have to get under the Valve Covers.

 

Right Click - Select All
Right Click - Copy
Right Click where you want the info to be and Click Paste

 

Alan,
Thanks again for the schematic. I hate to beg, but do you have pages 27-1 and 27-2? According to the last page you sent, those pages show the IDM power relay wiring.

 

Any updates guys, I am having the same problem...

 

This idea might be a little out there, but it proved to be the culprit in my intermittant starting problem. The motor would crank fine but simply never start. I noticed that sometimes the voltage would sag from the 14V range to maybe 9V or so. After checking battery cells, ground wires, etc, the problem was a hairline crack in one of the battery post clamps. The bolts appeared tight on all four clamps, but putting a wrench on them revealed that one would go tighter - to the point of exposing the crack.

 

Thanks for the info. After talking to a Ford Mechanic, I learned that the IDM will not send 110 volts out to the injectors until the high pressure oil pump builds pressure. I connected a high pressure guage per his instructions and found my hpop not building pressure at all. I will replace it as soon as I scrape up the money. I'll keep y'all posted.

 

Hey guys,

Mine sputtered and stopped on me last Friday night. I couldn't get it started. She cranked with great power, but never wanted to fire......I replaced the CPS, then checked all the fuses and relays, then ran all my AutoEnginuity checks on it. I got a bunch of codes, but I needed my truck soon, so I towed it to the Ford Dealer. I told them to check the UVC harness and all the wiring, and everything looked good to them

The diesel tech and the Ford dealer tested my fuel pump and it was not outputing. They replaced the pump ($594 including tow and tax). This WAS a job I should have done myself (a lot cheaper), but I needed the truck fast and didn't have time to work on it. I just drove it from the dealer to work and she ran just fine. I hope she keeps starting for me in the next few days, b/c these problems can be intermittent and could pop up again. I REALLY hope it was my fuel pump and the problem is REALLY solved. I'll keep ya'll posted.

Thanks,

 

I dont know if this would work, but couldnt you try taking a PCM or IDM out of another similar truck or try yours in another truck and see if the problem is solved. I guess if you dont know anyone though that has a similar truck this isnt as easy as it sounds.

 

have you changed the oil in it. I have seen trucks that would not start but did after they got fresh oil in them. Also, is your tank full of fuel? I have found it is important to have a full tank of fuel and a fresh filter when trying to diagnose these types of problems.