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Discussion Starter · #101 ·
Hello!
Glad you got it up and rolling!

When this happens it's caused by an intermittent loss of connection to the injector. As a safety feature the ECM turns off 4 injectors and only runs on 4 injectors to prevent damage. The injector solenoid going bad and making the ECM think that it lost connection is extremely rare. Chances are the plug is just loose. Replacing the pigtail with GMs updated harness will essentially bide you some time until it happens again. GM looked at it as a design issue with how short the wire is going to the plug. However the connector itself is what is actually loose and causing the intermittent connection. So no, replacing the pigtail won't fully cure the problem, but it may prolong it until the new connector loosens up.

The codes staying on is sign that the ECM sees something wrong with the circuit itself. Being as to how it won't go away and the truck still runs and doesn't go into tractor mode it's not shorting to ground anywhere due to the harness rubbing through, but the power wire feeding the injector may have a high level of resistance or the injector solenoid is failing.

Personally I feel the ice pick method provides the tightest crimp to the injectors and keeps them tighter than the new connector does. A connector that has been ice picked is significantly harder to push him onto the injector connection than a brand new connector is.

Hope this helps clarify your issues a little bit. If anything is unclear or you need more direction please post back here.

Happy trucking! 🤘


I know I am picking up an old thread. This finally happened to me yesterday. After over 15 years since the truck was manufactured. I was in a hurry so did this instead:

Basically pushing the female connector in and crimping it. I still have some questions about either method:

1. Does this mean that the injector is confirmed good and its just the connector ? Or is it that the FICM relearned to run it with 7 injectors instead.
2. My codes are staying on even after clearing them (P0207 and P2146). Truck runs fine and no longer have the tractor sound. Should replacing with new pigtail connector help remove the codes ?
3. Whats the difference between the two methods ? One shown on youtube vs one shown in this thread ?
4. Should I even bother to do anything after the icepick fix ? I mean its crimped on good and don't see point on changing the pigtail or the harness.
 

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Discussion Starter · #102 ·
@Hook'em_Horns!
Hope all is well. Is there anyway this can be made into a sticky? I don't want to lose the pictures/info on this post if possible. Thanks!
 

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Revivng a great post, and looking for help! My 2002 LB7 is throwing P0201 and P0203, running at about 95% power feels like and only slightly "revving" at very low rpms and was having "long crank starts" when hot. Now won't start at all and I'm stuck in Costa Rica at a shop who claims I need to replace the injectors. I posted earlier and a responder linked me to this post.

I'm going to try the ice pick on 1 and 3 tomorrow.

Couple questions - 1. what might be causing the no start now? Pretty sure these Costa Rican mechanics are wrong and I don't need to replace but really don't understand why it is not starting suddenly. Sidenote - it will take a minimum of 1 month to get the injectors and cost $400/each!

2. Seems like this problem is very common for LLY, is it as common for LB7? Do you see many LB7s or should we look elsewhere in particular for a ground fault

3. Any tips on what I should ask these mechanics as to why they are so sure I need new injectors? The motor was scanned for codes 3 weeks earlier and these didn't appear and now suddenly 2 injectors failed at the same time?

Thanks everyone! I'm learning on the fly and really hope to get this running as it's our camper/home and we need to get it back to Colorado as soon as borders open!
 

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Hello all-
I decided to put this together after finding that when i needed a how to on how to perform the injector ice pick operation in a time of need on the side of the road i was surprised that i could find very little information on this site that clearly depicted how to do this with decent pictures . So i hope this may help someone else that may resort to using it in a time of need- because we all know the side of the road isn't a good place to be.

Does your truck sound like this?

How To Ice Pick Your Injector Harness:

1: Obtain the needed tools. I found that it is relatively easy to find a set of "ice picks" or pick and hook set at my local Wal-Mart. I used a slightly smaller ice pick on mine. you do not want to use a large ice pick for this operation. If the ice pick is as big around as a pencil then it is too big, but one as big around as a toothpick typically works better. Some may agree with this some may not, but it's what i have found that works the best while minimizing the amount of water that could potentially get into the connector after the fact when the engine is being washed/ cleaned, ETC. The biggest thing is that the ice pick is sharp. For those of you that do not have a local Wal-Mart this essential tool can typically be obtained at any local hardware store. I found a set at my local Wal-Mart for less than $5 for a set of 5. And of course the brand name of the ice picks is Dura-Max.. lol...





2: The first thing you are going to want to do to ice pick your injectors to know where your injectors are.. haha... The picture below shows a far away view of the approximate location on the aluminum heads of where the injectors are located. You will be looking for a black plastic electrical connector with two wires coming out of it as seen in the pictures below.







3: Decide which injectors to perform the ice picking operation to. If you are stuck on the side of the road i would hit the problem injectors first to get you up and running. This would be the injector closest to the front of the truck on the driver's side, and the injector closest to the firewall on the passenger side (cylinder 2 and 7). Those two are typically the problem child injectors because of the angle of the wire harness connector that is attached to the injector. The extra pre-load caused by the connector design typically causes these to become loose first.

Here's how the cylinders are arranged FYI:
The passenger side is 1,3,5,7 front to back
The driver side is 2,4,6,8 front to back

4: To remove the injector plug push down on the black plastic tab on the top of the connector and push the connector plug in towards the injector and then pull back on the connector to pull it off of the injector. You may have to wiggle these a little bit to get them off, but they should come off very easily. Do not pull or yank on the wires or use excessive force here.



5: Once the plug is off of the injector flip the injector connection to the side depicted in the picture below. The set of "snake bites" in the picture is where i have already performed this on my injector connections and aides you in locating where the ice pick should be inserted into the injector plug. This is the side you want to perform the "ice pick" operation. The side to ice pick has the writing on it to make it easier to locate.

Side to Ice Pick:



Side Not to Ice Pick:



6: Once you figure out the orientation of the connector and are ready to perform the ice picking operation be aware that this can be potentially dangerous. When performing the ice picking the ice pick can slip off the injector or go through the injector and pierce your hand or anything behind it- other wires, radiator hoses, etc.- and believe me they are unforgiving as there usually a good bit of force behind the ice pick from you pushing on it when it happens.

7. Line the ice pick up on the connector as depicted below. There isn't a 100% exact spot on place to perform this on the injector but the object is to be VERY close to the location depicted in the picture. The object here is to put the pointed end of the ice pick on the plastic injector connector and shove it through the side of the connector until it is almost to the other side- there is no need to push the pick through any further through than the last picture under step 7 shows. By doing this you are effectively "re-crimping" the loose connector inside the injector allowing it to make a good connection and when this is done it also forces the plastic that is dimpled in to more effectively hold the connector in place. You will have to do this twice for each connector as you can see the two small holes in the side of the connector below as you have to do this for each of the two wires inside the connector.









8. After you have finished ice picking the injector connector you should have two holes in it as shown below. You are now done with the ice pick operation.



9. Before re-connecting the injector you can optionally put a small amount of die-electric grease into the end of the injector connector where the metal spades are to protect the connector from corrosion and the elements and to ensure a better connection. After this is completed make sure the small orange rectangle shaped o-ring is still on the connector and then plug the connector back into the injector. Take a look around and make sure the wire isn't rubbing anything around it. If it is this would be a good time to go ahead and tape it up or put some new wire loom on it as it gets brittle and falls off due to the heat in the engine bay which exposes the delicate wiring.

10. After you have made all of your connections and performed the ice picking operation on the needed connectors start the truck up and make sure it runs correctly. Throw the ice pick in your glove box in case you need it on the side of the road.

Hope this helps and as always if i missed something leave a comment and let me know so i can update so this can be made available for others to reference that may not know how to do this. We were all new to the Duramax at one point.. haha.

Happy Trucking.. :gearjamin
how long does ice pick method usually work? just had to do it to my lly but just curious to if i should go buy new pigtails while im ahead.
 

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Discussion Starter · #105 ·
how long does ice pick method usually work? just had to do it to my lly but just curious to if i should go buy new pigtails while im ahead.
I did mine about 100K ago and haven't had an issue since- even after swapping the engine.
 

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does driving on 4cylinders with that rattling tractor sound hurt the engine if you drive it awhile? The check engine light came on for me on my 05 pulling my race car trailer and power went to nothing but I managed to limp it home for 40 miles. The sound was worse at idle and I tried to keep it out of that range. I figured it was an injector problem or it was in lamp home mode for some reason. Hope I didn't screw the damn thing up I'm going out to look at it tomorrow
 

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Discussion Starter · #107 ·
does driving on 4cylinders with that rattling tractor sound hurt the engine if you drive it awhile? The check engine light came on for me on my 05 pulling my race car trailer and power went to nothing but I managed to limp it home for 40 miles. The sound was worse at idle and I tried to keep it out of that range. I figured it was an injector problem or it was in lamp home mode for some reason. Hope I didn't screw the damn thing up I'm going out to look at it tomorrow
No it should be fine. The engine is still mostly balanced even running on 4 cylinders. Try wiggling all the injector plugs one by one then starting it to see if it goes away. You can somewhat pinpoint which one it is by doing that to see if it goes away.
 

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thanks, I went out and checked 2 and 7 today. 2 had evidence of corrosion so I cleaned and recrimped the terminals. started it up and it ran fine. im out of town and I dont have access to my diagnostic equipment so I went down to oreilly and it had 2codes for the number 1 injector so I cleaned and crimped that one although it was perfectly clean. the check engine light went off after a few starts and its running fine now. I didnt wiggle the terminals while it was running but thats a good idea
 

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Discussion Starter · #109 ·
Glad you got her going brother. Keep that crimp tool in the glovebox and you'll never be stuck again 🤘
 
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