I have just changed my o rings on every injector because they were leaking oil into the head. Also changed uvch and soldered in new pigtails because pins were burnt up.
After I got everything back together I went to fire it up, I was expecting a long crank time in order to purge air out of the hpo system, but after many crank attempts It still won’t start.

Using a Bluetooth dongle and FORScan I’m seeing
~2000 icp psi
~190 rpm
~1.8ms fuelpw
~11.3 module voltage


I also ohm tested the wiring harness at the idm connector using a procedure I found on here, everything omhed out as it should have.

so I’m starting to think that the idm may be bad? The truck started and ran fine before this, except for running a little rough when cold. Seems strange that the idm would just suddenly go back like that.
and suggestions on where to look next would be greatly appreciated. Thanks.

 

Are you seeing any smoke put the exhaust while cranking?

 

No smoke out of the exhaust, also no oil out of the exhaust ports on the injectors. I don’t think they are firing at all.

 

I know that you said that you verified that the wiring is correct using some ohm test procedure, but I have to suspect the issue is with something related to the changes that you made rather than the IDM failing at that exact moment. I am not a mechanic or anything. I am just this guy over here, but I would think that if that were the case, you would need to either buy a lottery ticket (or avoid buying any lottery tickets ever, depending on how you look at it), or be able to articulate how the changes you made might cause the IDM to fail. Could something that happened when you were soldering in new pigtails that could have caused the IDM to fail?

 

[QUOTE=BuckHammer;21214424]I know that you said that you verified that the wiring is correct using some ohm test procedure, but I have to suspect the issue is with something related to the changes that you made rather than the IDM failing at that exact moment. QUOTE

The reason I don’t think the new pigtail or wiring is the problem is because I’ve had it running after I soldered in the new pigtails.
I originally took the truck apart to replace glow plugs, uvch, new pigtails, and put a shim kit on injectors. After I completed this I started the truck with the valve covers off to make sure everything looked ok, and It cranked right up. But then I noticed some injectors leaking oil into the head. So I pulled all 8 and replaced the o rings, and haven’t been able to get it to start since removing and replacing o rings.

 

Another thing worth mentioning, when I had the injectors out I found that there was some type of gunk on the fuel section of the injectors, I’ll attach some pictures. I cleaned it off with a scotchbrite and then sprayed everything off with brake parts cleaner very thoroughly, I don’t know if maybe some of this gunk worked its way inside the injectors and is causing a problem. I also don’t know what caused this gunk in the first place.

 

I know there's alot of air that needs purged after pulling injectors. Have you verified the hpop reservoir is full. Does the icp pressure change? Sometimes if they're failing the system could revert to using default values instead of actual.

I also am skeptical it's the idm. Seen alot of folks with starting issues on here, I don't remember any of them actually being a bad idm as the root cause.

Usually, my shot in the dark would be the CPS. Those have been known to cause all sorts of havoc.

Are you slaving the truck off when cranking? Just to verify it's got enough cranking power?

 

Hpop reservoir is full, the icp pressure starts at 0 and then jumps up to 2500 psi after maybe 5-10 seconds of cranking. I also tried starting the truck with the icp unplugged, but it made no difference.

and I get an rpm reading of 195 when cranking, doesn’t that rule out the cps as the problem? I thought a bad cps would read 0rpm.

And sorry but what does “slaving off the truck” mean?
I am jumping it to two other batteries when cranking, and I do see around 11 volts when cranking.

 

Have you tried buzzing the injectors with your scan tool?

 

Yes I have done a buzz test, number 5 sounded a little softer than the rest, the other 7 sounded good. I did get a whole slew of codes after the buzz test, I’ll paste them below. I’m thinking all the codes saying “high to low side fault” got saved to the idm when I cranked the engine over with the glow plugs removed and the ucvh disconnected in order to clear the cylinders of oil. But I can’t figure out how to clear them from the idm to see if they return.


=== Log ===

(OK) [19:59:13.720] KOEO Injector Electrical Self Test has been started

(WARN) [19:59:31.708] Test completed, found DTCs: P1271, P1272, P1277, P1273, P1274, P1275, P1276, P1278, P1293, P1294

===

=== DTC ===

P1271 - Cylinder #1 High To Low Side Fault



Diagnostic Trouble Code details



Cylinder #1 High To Low Side Fault



Follow the routines in the service manual to resolve the DTC listed.



P1272 - Cylinder #2 High To Low Side Fault



Diagnostic Trouble Code details



Cylinder #2 High To Low Side Fault



Follow the routines in the service manual to resolve the DTC listed.



P1277 - Cylinder #7 High To Low Side Fault



Diagnostic Trouble Code details



Cylinder #7 High To Low Side Fault



Follow the routines in the service manual to resolve the DTC listed.



P1273 - Cylinder #3 High To Low Side Fault



Diagnostic Trouble Code details



Cylinder #3 High To Low Side Fault



Follow the routines in the service manual to resolve the DTC listed.



P1274 - Cylinder #4 High To Low Side Fault



Diagnostic Trouble Code details



Cylinder #4 High To Low Side Fault



Follow the routines in the service manual to resolve the DTC listed.



P1275 - Cylinder #5 High To Low Side Fault



Diagnostic Trouble Code details



Cylinder #5 High To Low Side Fault



Follow the routines in the service manual to resolve the DTC listed.



P1276 - Cylinder #6 High To Low Side Fault



Diagnostic Trouble Code details



Cylinder #6 High To Low Side Fault



Follow the routines in the service manual to resolve the DTC listed.



P1278 - Cylinder #8 High To Low Side Fault



Diagnostic Trouble Code details



Cylinder #8 High To Low Side Fault



Follow the routines in the service manual to resolve the DTC listed.



P1293 - Injector High Side Open - Bank 1



Diagnostic Trouble Code details



Injector High Side Open - Bank 1



Follow the routines in the service manual to resolve the DTC listed.



P1294 - Injector High Side Open - Bank 2



Diagnostic Trouble Code details



Injector High Side Open - Bank 2



Follow the routines in the service manual to resolve the DTC listed.



===

 

Something else I’ve just discovered that seems wrong, I tried cranking with icp unplugged and FORScan showed icp psi jump up to 2500 as soon as I turned the key (still no start)
I thought that with icp unplugged the computer should default to 700psi?

 

Are you thinking that all of those codes are leftover from when you had the UVCH disconnected? FORScan ought to be able to clear diagnostic trouble codes. If not, I would think that disconnecting the batteries for a little while should do it.

 

Yea I was guessing they are leftover because the wiring harness ohmed out correctly when I tested it. So I don’t think there are any disconnects or shorts between the idm and the injectors.
I’ve been able to clear regular diagnostic codes with FORScan, but I didn’t see a way to clear the idm codes (the ones that show after a buzz test).
I left the batteries disconnected this morning, I’ll do another buzz test when I get home and see if the codes return.

 

Well I was able to get the truck to start today, and I think I’ve discovered my problem(s). But I’m not sure I’ve solved them.
firstly, I discovered today the reason the truck wouldn’t start was because injector #6 was still leaking oil into the head and preventing the hp oil system to reach the required 500psi to fire the injectors. So I pulled that injector to see if I messed up on the o ring install, but everything looked good. So then I pulled the #4 injector and swapped it with the #6 injector to see if the leak followed the injector. After I swapped the injectors the truck started after about 10 seconds of cranking. Icp while idling reads about 650 psi. The interesting thing is all four drivers side injectors seem to be weeping some oil from the base of the injector, which seems bad. But the icp reading is fine so idk.
is there any reason the injectors would leak oil other than bad o rings? Because I don’t think that is the issue, they’re all brand new!

The second weird thing I’ve found is when unplugging the icp sensor the truck defaults to 2465.7psi. As far as I understand it is supposed to default to 700psi, so im not sure why mine is wrong. This is also why I thought I had plenty of oil pressure, FORScan would read zero for about 10 seconds while cranking, then jump to 2465.7 (I guess after reading zero for too long it goes to default)
sorry for the long post, but I’m confused by these results, and suggestion would be much appreciated.

 

Did you use Motorcraft O-rings?