Nadthomas 2007 Yukon Denali 200k Mile Re-build

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nadthomas

nadthomas

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Teasing you for too long with no finish? :shrug:


I would love to be done with it at this point too.
 

iamdub

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Teasing you for too long with no finish? :shrug:


I would love to be done with it at this point too.

My heart and balls ache for you, bro.

Seriously, though. Seeing it come to this is a buzzkill. I hope it's nothing expensive or lengthy. I'm planning an AFM delete and may end up doing something very similar as you because mine's currently at 193K. Well, similar as in the work performed. I hope to learn from whatever happened with this failure and not experience it myself. Anxiously awaiting progress with fingers crossed for you...
 
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nadthomas

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Thanks for the support. Yeah, I was pretty disheartened last night when I found I lost communication with the TCM again. The biggest problems with these electrical issues is having the right tools and info to diagnose. A multi-meter only gets you so far when it comes to CAN Bus issues. Maybe I need to dig more into the functions of the Tech2, but it seems somewhat limited as well. Additionally, I don't have any of wiring diagrams. So, I have to search forums and watch a bunch of youtube videos to piece together things I can try. If I had one of the $4k Snap-On diagnostic scanners, and a copy of all the GM wiring diagrams I'm sure I could figure it out.
 
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nadthomas

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UPDATE!!! All is not lost, and I'm finally almost done with this part of the rebuild. My friends shop had it for a little over a month, kind of working on it on the side to help keep costs down. They went over a good portion of the wiring harness, and eventually came to the conclusion the TCM was the source of the problem. They found 2-3 pins on the TCM were bent slightly. I'm not sure if that was the whole of the problem, or if something else happened to the TCM, but a new TCM was installed and it fired right up. Unfortunately, the shop was not able to program the TCM, so I still have that to deal with. Additionally, when they fired it up they found low oil pressure. :banghead:

I paid them to due some basic diagnostics, and they verified with a mechanical gauge that the dash gauge was accurate, and they also swapped in another oil pressure sensor. So, it quickly came to the point that it was going to be a lot of labor for them to diagnose any further. I didn't want to spend my free time over the holidays tearing it apart again, but that is exactly what I did. After getting it towed home, and tearing apart the front end again. I inspected the oil pickup tube o-ring and replaced the oil pump again, but this time with a Melling 10355 high volume/high pressure pump. With the new pump installed cold startup pressure was still only 20psi. :banghead: :banghead:

Defeated, demoralized, and out of ideas I hoped someone on here could school me on what I did wrong. Fortunately, someone thought of the small circular gaskets on the bottom of the valley cover. I'm not sure if these are on all version of the valley cover, or just the non-AFM/non-DOD vehicles. Hindsight, I noticed these gaskets when I was putting things back together, but realized I didn't order replacements. Thought to myself "They will be fine". Then slapped on the valley cover with a new main gasket, and old circular gaskets, and then immediately forgot all about hem. Once I installed some new gasket oil pressure with the new pump is now 65-70psi at startup. :chewie:

In total these hiccups have cost an additional $1300 in parts and labor. Not to mention several extra days in the garage. I hope to finish putting it all back together this weekend. Then I have to see how much the dealership down the road wants to **** me to program the TCM. o_O
 

kbuskill

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UPDATE!!! All is not lost, and I'm finally almost done with this part of the rebuild. My friends shop had it for a little over a month, kind of working on it on the side to help keep costs down. They went over a good portion of the wiring harness, and eventually came to the conclusion the TCM was the source of the problem. They found 2-3 pins on the TCM were bent slightly. I'm not sure if that was the whole of the problem, or if something else happened to the TCM, but a new TCM was installed and it fired right up. Unfortunately, the shop was not able to program the TCM, so I still have that to deal with. Additionally, when they fired it up they found low oil pressure. :banghead:

I paid them to due some basic diagnostics, and they verified with a mechanical gauge that the dash gauge was accurate, and they also swapped in another oil pressure sensor. So, it quickly came to the point that it was going to be a lot of labor for them to diagnose any further. I didn't want to spend my free time over the holidays tearing it apart again, but that is exactly what I did. After getting it towed home, and tearing apart the front end again. I inspected the oil pickup tube o-ring and replaced the oil pump again, but this time with a Melling 10355 high volume/high pressure pump. With the new pump installed cold startup pressure was still only 20psi. :banghead: :banghead:

Defeated, demoralized, and out of ideas I hoped someone on here could school me on what I did wrong. Fortunately, someone thought of the small circular gaskets on the bottom of the valley cover. I'm not sure if these are on all version of the valley cover, or just the non-AFM/non-DOD vehicles. Hindsight, I noticed these gaskets when I was putting things back together, but realized I didn't order replacements. Thought to myself "They will be fine". Then slapped on the valley cover with a new main gasket, and old circular gaskets, and then immediately forgot all about hem. Once I installed some new gasket oil pressure with the new pump is now 65-70psi at startup. :chewie:

In total these hiccups have cost an additional $1300 in parts and labor. Not to mention several extra days in the garage. I hope to finish putting it all back together this weekend. Then I have to see how much the dealership down the road wants to **** me to program the TCM. o_O

Not to add to your list of things to fix BUT...

Don't be surprised if, after you start driving it again, you end up with a check engine light for P0521 Engine Oil Pressure Sensor/Switch Range/Performance.

After installing the same oil pump I ended up with this code. Changed oil pressure sensor and still had the same issue. The ECM thinks the oil pressure is too high.

I assume someone with HPtuners/EFIlive might be able to find the parameters within the ECM to change what the computer expects to see but when I asked Black bear about it they told me that the only thing they could do was cause the ECM to ignore the input from the oil pressure sensor so the CEL wouldn't set. I was unwilling to do that for fear of losing pressure and not getting a warning (wife's truck).

If you have that issue let me know and I will share how I alleviated that issue.
 
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nadthomas

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Not to add to your list of things to fix BUT...

Don't be surprised if, after you start driving it again, you end up with a check engine light for P0521 Engine Oil Pressure Sensor/Switch Range/Performance.

After installing the same oil pump I ended up with this code. Changed oil pressure sensor and still had the same issue. The ECM thinks the oil pressure is too high.

I assume someone with HPtuners/EFIlive might be able to find the parameters within the ECM to change what the computer expects to see but when I asked Black bear about it they told me that the only thing they could do was cause the ECM to ignore the input from the oil pressure sensor so the CEL wouldn't set. I was unwilling to do that for fear of losing pressure and not getting a warning (wife's truck).

If you have that issue let me know and I will share how I alleviated that issue.

Yeah. I saw you previously mentioned you got a CEL because the pressure is too high. I did swap to the lower pressure spring that came with it (I believe it was yellow) before installing it. The instructions said it should be about 8-10psi lower. Hopefully that will do the trick. I have not let it run for more then a minute since it has no water pump, radiator, etc installed at the moment.
 
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nadthomas

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I got it all back together this weekend, and took it for a trip around the block. Everything seems good, except that it won't go past 2k RPM, but I'm pretty sure that is expected since the TCM still needs to be programmed. Dealership just down the road from my house said 1 hour @ $110 to program it. So, I'll be dropping it off there at some point this week.
 

iamdub

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I got it all back together this weekend, and took it for a trip around the block. Everything seems good, except that it won't go past 2k RPM, but I'm pretty sure that is expected since the TCM still needs to be programmed. Dealership just down the road from my house said 1 hour @ $110 to program it. So, I'll be dropping it off there at some point this week.

*Fingers crossed
 
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nadthomas

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The dealership programmed the TCM yesterday, and all appears to be well. At least from what I could tell on the 3 mile drive home. There was a check engine light on when I dropped it off yesterday, but that could have been from any number of things at the time. I honestly don't recall if it was still on when I drove it home. I need to do some increasing longer shake down trips with it, and drive it to work for a week before handing it back over to my wife.

Then its time to plan for the suspension overhaul.
 

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