What did you do to your NNBS GMT900 Tahoe/Yukon Today?

[justchecking]

Did you just replace the gears?

My passenger side motor went out about 2 years ago and I just swapped the motor housing out with a new one. I still have the old one sitting on a shelf. I thought about disassembling it and fixing it and either keeping for a spare or selling.

I used the gruven kit with metal gear which requires a new gruven motor as well so it doesn’t short out thru the metal. I also had the eBay (I think) nylon replacement which I think would have worked just as well with the old motor but much cheaper.

 

[Doubeleive]

I ordered a new one for delivery tomorrow regardless, I had swapped in my spare that had about 70k on before we left for our trip and it threw a maf code & misifre today so I swapped in the other one I had with about 70k on it and no codes at all but it's still dogging on me hard, feels like 4 cyl and it's causing it to not shift right.

 

[89Suburban]

I ordered a new one for delivery tomorrow regardless, I had swapped in my spare that had about 70k on before we left for our trip and it threw a maf code & misifre today so I swapped in the other one I had with about 70k on it and no codes at all but it's still dogging on me hard, feels like 4 cyl and it's causing it to not shift right.

No rest for the weary

 

[j91z28d1]

They sent the revised tune back, and it addressed the P0010 CEL... I assume they disabled the error code due to no VVT present. They said there was also minor tweaks to the cam, which seems to have improved the starting issue.

It was physically ready to run the engine yesterday, but it was idling.... not very well, and wouldn't restart after killing the engine.

glad it was just a tune issue

 

[j91z28d1]

I used the gruven kit with metal gear which requires a new gruven motor as well so it doesn’t short out thru the metal. I also had the eBay (I think) nylon replacement which I think would have worked just as well with the old motor but much cheaper.

I did the cheap metal gears off Amazon. no motors needed, on the stock ones the housing is also negative and then when it flip direction the the neg post becomes positive it shorts out since the case is ground thru the gears. but it's just a little metal tab you can cut off, there's a video somewhere I saw of it when I did mine.


I also forgot on the 2nd one, had it back together and hit the button before I remembered. it burnt it's own ground connection on the 2nd try and started working. haha.

been working fine since.

 

[j91z28d1]

not the greatest video but is this my maf dogging me out ?

I'm not seeing it? what am I missing.

 

[Doubeleive]

I'm not seeing it? what am I missing.

look at my 2nd video
basically it's got no power, not shifting right, really cropped up worse when i put my other maf in there which is not throwing a code but also not working right.
I can tell the difference between the the 2 maf's and both should be fine and performance should be equal. but it's not

 

[Doubeleive]

when I revved it up in the 1st video it should have shifted and took off but it just hung in low gear and barely accelerated, like a freakin turtle.

 

[j91z28d1]

ahh I watched it but guess I'm not sure what the maf should be doing in that format. seemed to follow the TPS ish. but if a new maf fixed it. cool.


so these Gen 4 ecm's use a timing table based off rpm and grams/sec maf instead of older rpm vs map. there's some more fuzzy math where they can blend the 2 for fast response time since a maf is slow but yeah, a maf signal out of wack can put you in a completely different part of the timing map then you're normally in.

my own I cleaned the maf sensor and it lowered the maf signal a just a bit and it put me in a higher timing by a few degrees, I didn't expect that at the time and had to go research on the hpt board. so yeah definitely could make it a dog, or make the knock retard go max too if it was so off it was running more than needed.

 

[Doubeleive]

ahh I watched it but guess I'm not sure what the maf should be doing in that format. seemed to follow the TPS ish. but if a new maf fixed it. cool.


so these Gen 4 ecm's use a timing table based off rpm and grams/sec maf instead of older rpm vs map. there's some more fuzzy math where they can blend the 2 for fast response time since a maf is slow but yeah, a maf signal out of wack can put you in a completely different part of the timing map then you're normally in.

my own I cleaned the maf sensor and it lowered the maf signal a just a bit and it put me in a higher timing by a few degrees, I didn't expect that at the time and had to go research on the hpt board. so yeah definitely could make it a dog, or make the knock retard go max too if it was so off it was running more than needed.

I won't know if a new one will fix it until tomorrow whenever Amazon delivers it. I am just assuming that it is the problem, in the 2nd video when I had it revved to 1700rpm the grams are only showing 13 on the maf. Can't really get good run with the tech2 connected I think I need a new connector it will loose connection with the slightest bump