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

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j91z28d1

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pulled it in, put it up in the air, took out the block drain plug. I guess I'm officially doing water pump, hoses, T's and fresh fluid.

looked at how to pull the bottom radiator hose off without making all of the mess. cleaned up and walked back inside.. it's to hot for that mess tonight haha.

gm.. drain plug wtf haha.
 

Charlie207

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Replaced intake manifold gaskets, and finally got that exhaust clamp in the driver's side. It looks like the oil pressure sensor was leaking oil, so I took it out cleaned all the surfaces, and retorqued to spec. Hopefully it seals and stays dry.

I removed the stupid plastic shield on the back of the intake manifold, so replacing the sensor should be easier if it comes to that.

The engine runs quieter, and I'm guessing the old intake manifold gaskets were leaking a little. They were wore out.

Was a bit of a mess.

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Sparksalot

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Replaced intake manifold gaskets, and finally got that exhaust clamp in the driver's side. It looks like the oil pressure sensor was leaking oil, so I took it out cleaned all the surfaces, and retorqued to spec. Hopefully it seals and stays dry.

I removed the stupid plastic shield on the back of the intake manifold, so replacing the sensor should be easier if it comes to that.

The engine runs quieter, and I'm guessing the old intake manifold gaskets were leaking a little. They were wore out.

Was a bit of a mess.

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Didja have a squirrel nesting in there?
 

j91z28d1

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I see now why those firewall T's are such a pain.. at least on mine, gm put some kinda friction material over the aluminum lines running to the back, I'm guessing incase they rub on the tranny dip stick? but they push them all the way up under the release tabs. so you can't squeeze them. everything else came apart fine, till I got to that and ended up clipping the fittings. blah.

the oem hoses seem good quality, if it wasn't for these plastic things, I'd say there no reason to touch them. at 150k they look and feel like better quality than the new junk I'm putting on haha. oh well. got all apart, looks like I actually have everything but 3 spring clamps. I'll put it back together tomorrow.

I really need to ac my garage. this is ridiculous
 

Charlie207

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Out of curiosity, is there a replacement VLOM (valley lifter oil manifold) gasket, or does the entire part need to be replaced?

I'm still in "oil leak investigation" mode, and figure since I just replaced the intake manifold gaskets, and had it all apart, I should think about replacing the other parts .... Now that it's all back together.

:rolleyes:
 
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Replaced intake manifold gaskets, and finally got that exhaust clamp in the driver's side. It looks like the oil pressure sensor was leaking oil, so I took it out cleaned all the surfaces, and retorqued to spec. Hopefully it seals and stays dry.

I removed the stupid plastic shield on the back of the intake manifold, so replacing the sensor should be easier if it comes to that.

The engine runs quieter, and I'm guessing the old intake manifold gaskets were leaking a little. They were wore out.

Was a bit of a mess.

View attachment 406448
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View attachment 406451
Why is that plastic shield by the oil sensor there anyway? Does it unbolt or did you just cut it at the base?
 

wjburken

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Out of curiosity, is there a replacement VLOM (valley lifter oil manifold) gasket, or does the entire part need to be replaced?

I'm still in "oil leak investigation" mode, and figure since I just replaced the intake manifold gaskets, and had it all apart, I should think about replacing the other parts .... Now that it's all back together.

:rolleyes:
Yes…
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mikeyss

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Why is that plastic shield by the oil sensor there anyway? Does it unbolt or did you just cut it at the base?
I left mine off when I replaced my engine. There was one bolt holding it onto the intake. I'm guessing that the shield is for noise blocking because there's a foam piece glued to it.
 

Charlie207

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Also, just slammed this transfer case skidplate up into the transmission crossmember. The factory holes needed to be threaded, so I just used a spare bolt and impact gun to make the threads for the new bolts, and used a little anti-sieze to help stop the inevitable corrosion.

aEFerqI.jpg


Still waiting on Scamazon to deliver the other skid plate for the oil pan area.
 

Charlie207

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I left mine off when I replaced my engine. There was one bolt holding it onto the intake. I'm guessing that the shield is for noise blocking because there's a foam piece glued to it.

I assume it's for noise reduction also, but I couldn't tell the difference after winding out the engine last night.

Also, the sensor looks dry after 30 mins or so of running the engine, so hopefully that WAS the leaking issue.
 

Charlie207

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Why is that plastic shield by the oil sensor there anyway? Does it unbolt or did you just cut it at the base?

I removed the PCV hose on the rear of the intake manifold and removed the single 10mm nut that held it on. There is more foam on the inside of it, so I ass ume it's sound deadening/ rat nest material.
 

RooTBeeRthe1st

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Im going to drive it around in the hurricane to run some errands.

Edit:

I think when I drop the tank to put a bigger fuel pump, I might have to try that Holley Hydramat if I can get one that will fit in there nicely.
Sick of losing fuel pressure when I'm doing a cloverleaf on ramp at a third of a tank or less.
 
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Charlie207

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Im going to drive it around in the hurricane to run some errands.

Edit:

I think when I drop the tank to put a bigger fuel pump, I might have to try that Holley Hydramat if I can get one that will fit in there nicely.
Sick of losing fuel pressure when I'm doing a cloverleaf on ramp at a third of a tank or less.
What's the forecast?
 

RooTBeeRthe1st

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What's the forecast?
It was a cat for the other day, it's already downgraded to a tropical storm. And by the time it gets here it will probably still be 50 miles east of me. But this is the first hurricane that the West Coast has seen in about a hundred years and it was supposed to dump a stupid amount of rain and have very high sustained winds.
Looks like now that it's already above Mexico it has slowed all the way down to 70 miles an hour and under
And it has been raining here since around 2:00 a.m., but nothing crazy. Actually quite light rain.
 

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iamdub

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Im going to drive it around in the hurricane to run some errands.

Edit:

I think when I drop the tank to put a bigger fuel pump, I might have to try that Holley Hydramat if I can get one that will fit in there nicely.
Sick of losing fuel pressure when I'm doing a cloverleaf on ramp at a third of a tank or less.

I don't see a use for the HydraMat in our setups. The pump stays submerged in it's own "bucket", unless it's leaking. Performance cars, like the 'Vette that are tracked pull a lot more lateral Gs than you are in your Tahoe and they don't use or need things like the HydraMat.

I thought my fuel pump bucket was leaking out and allowing the pump to run dry on hard accelerations. The problem only occurred around 1/4 tank or less. When I replaced the pump/module assembly, I found that I had very little fuel in the tank. The pump and all was fine and wasn't running dry. It was the level sensor reporting that I had a lot more fuel than I actually did. The fuel was sloshing to the back of the tank and the fuel in the bucket was being used up, causing the sputtering. I tested the sensor and found it was within spec up until that 1/4 tank remaining area then it went to open circuit. The PCM was relying on the MPG, IDC and TPS, etc. to calculate the fuel remaining and operated the gauge accordingly.

Whatcha wanting a larger pump for, gonna boost it?
 
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