Considering DD'ing 350k mile LB7?

[DAVe3283]

Thanks for the help man. While I got you here, do you happen to know what the red jumper box that ties into battery and alternator is called/part #?

I'm pretty sure you're referring to part 12191376. Amazon has it for $21, but you might be able to find it cheaper somewhere else.

I don't know all this stuff off the top of my head; I just happened to order that exact part earlier this month

 

[fl0w3n]

I'm pretty sure you're referring to part 12191376. Amazon has it for $21, but you might be able to find it cheaper somewhere else.

I don't know all this stuff off the top of my head; I just happened to order that exact part earlier this month

Haha sure, instead of “hey Alexa” you’re turning into “hey Dave” for Duramax part numbers.


That’s exactly what I was looking for. Ordered a new cable from the alternator to that box previously, but then went to replace it at the box and it had fried something and melted part of the box and the terminal looked bad. Figured it wouldn’t be too much to just replace it.

 

[fl0w3n]

I was just thinking, since I need to clear the valley and get the intake horn off the turbo anyway, do you think I’d be able to pull the turbo out with the stock down pipe attached?

That might save me some big money if I can get that out and then work on removing the down pipe on the work bench.

 

[Mater86]

I just read through your whole thread I really hope your get this together and back up running. I see the headaches you ran into and I'm gathering my parts to do injectors soon. Seems like it wasn't to bad until you hit a wall doing the Cali to Federal swap. Don't give up your so close can't wait to see a video of it running.

 

[fl0w3n]

I just read through your whole thread I really hope your get this together and back up running. I see the headaches you ran into and I'm gathering my parts to do injectors soon. Seems like it wasn't to bad until you hit a wall doing the Cali to Federal swap. Don't give up your so close can't wait to see a video of it running.

It really wasn’t too bad, but definitely take some pictures along the way! I didn’t do a good enough job of that.

The difficulty definitely is coming from the swap.

Thank you, I really can’t wait to drive this thing again.

 

[fl0w3n]

Finally got a weekend coming up where I can get back on this thing. I fly to it Friday night and out Sunday night, but I think this is finally the weekend I get it started and can actually drive it down the street at least.

I want to stay organized so here’s a list of the remaining items:

This is what I need to do this weekend to get it running-

Swap Y bridge
Fan/clutch/shroud
Pipe cooling
Pipe intercooler/intake
Oil change/fomato valve
Coolant fill
Starter bolt
Install jumper box

Then, once it’s running I’m going to tow it to a shop to have them do-

Down pipe
Up pipe
Exhaust
Flash tune

Once I have it back, I can feel comfortable driving it the 300 miles north and should be able to knock this stuff out with the help of some buddies-

Lift pump
Wheel stud/lug nut (Stripped 1 pass front)
- order
Pull CV shafts (they’re shredded and don’t have a front DS anyway)
Jounce stops
- order upper
Driver motor mount
Adjust torsion bars
Alignment
- tie rods?
Mount Steelies/33s I have sitting in the garage
Swap CDT speakers in
Detail
Tint
Headlight/taillight?

 

[fl0w3n]

oh I need input - I swapped in a brand new AC Delco balancer, and I forgot in my parts stash at some point I bought one of those crank key fixing kits, where you can drill and tap the crank and balancer so it doesn’t spin. Is it even worth it at my sub 450hp power goals? I don’t remember why I thought I needed it when I originally bought it.

 

[clrussell]

oh I need input - I swapped in a brand new AC Delco balancer, and I forgot in my parts stash at some point I bought one of those crank key fixing kits, where you can drill and tap the crank and balancer so it doesn’t spin. Is it even worth it at my sub 450hp power goals? I don’t remember why I thought I needed it when I originally bought it.

I wouldn’t mess with it personally

 

[fl0w3n]

I wouldn’t mess with it personally

Thanks. That’s kinda what I figured and why I hadn’t done it yet.

 

[fl0w3n]

So I finally got it to a point where I’m ready to start it. But... like an idiot I dropped the wrench setting up the passenger battery and it arcd pretty good.

When I crank it says security, and then alternates between security and battery.

I tried disconnecting both negative terminals and the ignition 40a for 15 min to reset it, but no change.

Tried doing the 10min crank intervals, no change. Although after the first 10 min the security stopped showing up... but when I completed the cycle and tried starting, no go. Finally keyed off and back on, tried again, and security was back.

I’m leaving it over night with the negative terminals off and the ignition 40a unplugged.

Also, I’ve got quite a few codes... and the FPR is humming.

P0193
P0489
P0543
U1D21
C0121
C0400
P009A
B3421
P00F3

 

[fl0w3n]

Not much of an update... same thing in the morning after letting it sit all night. Although going to bed I was thinking about it and realized I never plugged in the fuel rail pressure sensor. Got that plugged in, no change.

I tried using my old original key I got the truck with and doing the learn procedure, same result. The keys I have now are GM cut from the dealership. Don’t know if it matters or not, but a reminder that my truck is manual locks/no remote entry.

Also found an alternate procedure from a company who sells pre programmed BCMs and he said you crank, wait 10 with key in run, key off then back to run (no crank), wait 10 with key in run, key off then back to run (no crank), wait 10 with key in run, key off then back to run and it should start then. I’m trying that now.

Also hooked up battery chargers to both batteries.

I think I might be losing some prime, but I don’t see where it’s going. I rebuilt the filter head and the lines all the way to the CP3 are brand new.

I’m still not sure if I should be chasing this security light, or if I have an actual problem somewhere. The security light doesn’t act like what other people describe.

 

[clrussell]

Not much of an update... same thing in the morning after letting it sit all night. Although going to bed I was thinking about it and realized I never plugged in the fuel rail pressure sensor. Got that plugged in, no change.

I tried using my old original key I got the truck with and doing the learn procedure, same result. The keys I have now are GM cut from the dealership. Don’t know if it matters or not, but a reminder that my truck is manual locks/no remote entry.

Also found an alternate procedure from a company who sells pre programmed BCMs and he said you crank, wait 10 with key in run, key off then back to run (no crank), wait 10 with key in run, key off then back to run (no crank), wait 10 with key in run, key off then back to run and it should start then. I’m trying that now.

Also hooked up battery chargers to both batteries.

I think I might be losing some prime, but I don’t see where it’s going. I rebuilt the filter head and the lines all the way to the CP3 are brand new.

I’m still not sure if I should be chasing this security light, or if I have an actual problem somewhere. The security light doesn’t act like what other people describe.

The relearn ( crank with key and leave on until the security light turns off, Turin key off, wait 5 sec, crank again and leave key on, wait until security light goes off, turn off for 5 sec, crank and leave key on until light goes off, then turn key off for 5 sec. then it should be relearned.

That should take care of your security light. Unless you have another issue.

 

[fl0w3n]

So that’s slightly different than the two ways I tried, and I don’t know when I’ll be back to try again unfortunately.

I was really hoping I would wrap up and just hit that key and have it jump to life... but, I also realize the truck was doing the same thing before I even started this whole project. I couldn’t get it started. I had figured it was the injectors or CP3 so I just tore in and started the project. So now I’m wondering if that’s a coincidence and it doesn’t have anything to do with the work I just did, or it was something else already.

 

[DAVe3283]

To really diagnose a no-start on a LB7 you need a scan tool. Then just start working through the prerequisites. Cranking RPM (good CMP & CKP signals), fuel pressure, main injection pulse, ECT+MAF+MAP+Baro are sane, anti-theft, etc. That's assuming the mechanical side is good (crank:cam timing, compression, etc.).

It actually takes quite a lot of things to be working perfectly before a Duramax will start. Those things are usually pretty darn reliable, but can occasionally go wrong.

Trying to diagnose this kind of issue without a good scan tool is going to be really difficult.

 

[fl0w3n]

To really diagnose a no-start on a LB7 you need a scan tool. Then just start working through the prerequisites. Cranking RPM (good CMP & CKP signals), fuel pressure, main injection pulse, ECT+MAF+MAP+Baro are sane, anti-theft, etc. That's assuming the mechanical side is good (crank:cam timing, compression, etc.).

It actually takes quite a lot of things to be working perfectly before a Duramax will start. Those things are usually pretty darn reliable, but can occasionally go wrong.

Trying to diagnose this kind of issue without a good scan tool is going to be really difficult.

Any suggestions on a home gamer model that will get the job done with j a budget? I hate to turn it over to a shop for the last mile, but it might be at that point due to all the circumstances

 

[DAVe3283]

Any suggestions on a home gamer model that will get the job done with j a budget? I hate to turn it over to a shop for the last mile, but it might be at that point due to all the circumstances

If you know someone in the area with an EFILive V2 or a GM Tech2, either one should work.

 

[fl0w3n]

If you know someone in the area with an EFILive V2 or a GM Tech2, either one should work.

What about the knock off pirated Tech 2’s?

I rented a V2 years ago from ATP when I tuned my LBZ, maybe I can just do that again while I figure it out... I could also knock out the tunes at that time.
I’d love to buy one, but there’s other more important things ahead of that

 

[DAVe3283]

What about the knock off pirated Tech 2’s?



I rented a V2 years ago from ATP when I tuned my LBZ, maybe I can just do that again while I figure it out... I could also knock out the tunes at that time.

I’d love to buy one, but there’s other more important things ahead of that

The Chinese clones of the Tech2 should work. I have one and it has treated me well.

 

[fl0w3n]

So I got my “tech 2”, in the next week or two I am going back down to finish this never ending project

I plan to start with figuring out how the fricken thing works, then checking that there’s no lockout security issues

If that’s fine, I figure diving into fuel and monitoring desired vs actual while cranking?

Other than that I’m lost for what else to check and figure out this no start.

 

[fl0w3n]

I guess you get what you pay for haha. First turned the new Tech 2 on and I could hardly read the screen because of white lines running up and down it. Messed around with contrast, turning it on/off, etc. finally got frustrated and hit it once, and it was readable for a second but then went back. So after many hitting squeezing and torquing then body, I found a wood clamp that placed just in the right spot it worked haha


Anyways, I’m hoping it was just as simple as I thought ... security. Hoping the other codes are just a result of all the work I did and not real