LLY injector issues

[Capt. Jim]

This might belong in another forum, but here goes:
I am getting these codes: P0201, P0204, P0206, P0207 and P2146. The Group A fuel injectors. Traced all my wiring numerous times, no chaffing, no moisture. Starting to suspect the FICM but don't knoew how to verify. Hate to just start changing parts out...
Possible I have no voltage to injectors causing all 4 on the bank to fail, or one bad injector circuit causing entire bank to shut down. Open to suggestions.

 

[zakkb787]

Look up lly ice pick. Do that first.

 

[Capt. Jim]

Did the ice pick with no luck and just changed all the pigtails, still no luck.

 

[Capt. Jim]

Pretty much tried everything I have read about on this and other forums. Working under the hood every day this week for at least several hours. Still cannot get bank A injectors (1, 4, 6 and 7) to fire. Thinking more about a faulty FICM but hate to buy one and have the same problem after installing new one. Truck starts but has the loud knocking noise. Can anyone that has replaced their FICM tell me what their symtoms were? Find it odd that entire bank of 4 injectors failed simultaneously while truck was running great. Running out of things to check here...

 

[Ne-max]

I rubbing wire or harness will wipe out the whole bank from firing

 

[2004LB7]

When one injector has an electrical issue the fcim will turn off the whole bank. At least you narrowed it down to only four injectors.

Test the wires from the ecm all the way to the injectors for resistance and shorts.

 

[Capt. Jim]

I checked entire harness for chaffing, found none. Looks like a previous owner did the prescriptive measures for this. Busy this week with boat show but going to trace each lead from FICM to affected injectors. Funny, I bought my '03 new and with over 325k miles on it now, have not had any of these issues.

 

[ikeG]

Wire diagram and a multimeter

Sent from my SM-G960U using Tapatalk

 

[Capt. Jim]

Ok....tested all my Bank 1 injector wires from connector C1 at the FICM to each of the 4 faulty injector pigtails, cylinders 1,2,4 and 7 with a continuity tester. All wires tested good as far as continuity and also not being shorted out to ground. Furthermore, none of the wires were shorted out to any other cylinder pigtail wires. (I could not test every wire within the common loom for shorting with the wires I was testing.) Also, I recently changed all 8 of my pigtail connectors after the ice pick trick did not work.

So, my question is this, do I have a bad injector in this bank or bad FICM? PO told me injectors were changed about 70k miles ago. Truck did not smoke, only had the surge at idle due to a bad FPR, which I changed. Be aware this engine failure of bank 1 injectors occurred about 20 minutes/5 miles after replacing the FPR. During that short period of time where engine was good, she seemed to be running perfect.

 

[2004LB7]

What kind of ohm readings did you get when testing the injector wires from the ecm side?

 

[Capt. Jim]

I did not test for resistance, only continuity. Will do tomorrow after work and let you know what I find.

When I replaced the pigtail connectors I maintained the same polarity. Was wondering if polarity matters on the connector.

 

[2004LB7]

Polarity shouldn't matter

 

[duramaxnate]

I just looked at all of my diagrams and books for this. Those four injectors get their supply voltage from FICM Con. C1 Pin 3 (ORANGE) (Cir. IC13) From there it is branched off the the four injectors, 1,4,6, and 7. so there is a possibility that that particular voltage output no longer works.

https://1drv.ms/b/s!AjZdFYjH3SCH0knTUQNu7UqKfXgn

Here is a link to the PDF in my OneDrive of the diagrams and pinouts for the FICM and injectors.

 

[Capt. Jim]

My first thoughts are indeed no power output at circuit C1pin 3. However, still wondering if one bad injector on that bank will give the codes for all 4 injectors as well as the code for the entire bank. Going to try this: unplugging one injector on my good bank 2 and seeing if it just gives me the code for that injector only as well as that entire bank output voltage. If it just gives the code for that injector, then it most likely indicates the output voltage problem at C1 pin3. If it spits codes for all injectors on bank 2, it can be an injector issue on bank 1. Thoughts?

 

[Capt. Jim]

Tonight I checked the resistance at the four pairs of wires that lead to the injectors on the affected bank. I checked them where they originate at the C1 connector on the FICM. All 4 ohmed out at .7 to .8 ohms. I don't know what they are supposed to be but at least they are consistant. Let me know if these values are acceptable.

After reassembly, I cleared all the codes and disconnected one injector connector on the good bank to see if it would code all injectors on that bank or just the disconnected one. Although it did shut down the entire bank, it only coded the cylinder I disconnected.

Compare this test to what is happening on my bad bank and it seems to point to my FICM, as all 4 cylinders on that bank send a code. Anyone else out there follow my logic or am I still missing something here? Getting ready to pull the trigger on a new control module.

 

[2004LB7]

That is a good way to check if the injectors are good. I would do that test with the other injectors to see if one or more cause different codes or just a code for the bank

It very well may be an FCIM

PS: those ohm readings look good to me

 

[Capt. Jim]

Finally got some spare time after work and did a little more trouble shooting. Still waiting for my service manual to arrive so just trying some things that come to mind. Tonight I checked the voltage on the supply voltage lines to both injector banks (A and B). I did this with the key in the ON position and got 7.5 volts on bank A and 8.5 volts on bank B. This is without the engine running. I don't know what the voltage should be but I am under the impression that it should be much greater than 12 volts, perhaps it may go higher once start up occurs, I don't know. Any other things to check to verify my FICM is the problem?
She will still start up with only bank B operating but has the loud tractor knock until she finally dies. Then I must clear the codes before she will restart again with only bank B.

 

[Capt. Jim]

Dropped off the FICM at a local shop here that tests/repairs them. Will report whet they find. As I was there, about 25 were dropped off by USPS for repair...

 

[Capt. Jim]

After checking everything I could, I found a local shop around the corner from me that refurbishes numerous control modules, including LLY's. After testing determined mine was indeed bad but rebuildable, they rebuilt mine for under $200 and it solved my problem. Truck now runs smooth and strong again.

 

[TheBac]

Now thats some good news, and you didnt have to go far to get it, either! Congrats!