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

[Doubeleive]

swapped plugs 4 & 7 and the misfire follows the plug, so #1 #5 #7 had misfires and now 1/4/5 have misfires
so something is going on creating a imbalance from bank 1 & bank 2

 

[j91z28d1]

4 on the left and 7 on the right, no little ballz on 4 but the inner electrode tip is much shorter
View attachment 431153

I'm pretty sure that plug on the left is toast. the special metal, I don't know if you're running platinum or iridium, but whatever was there is gone.

they do have some miles on them, probably best to start over with new set and check on them randomly to get a feeling how the engine is running.


from those I'd say you need higher octane fuel or give up some hp with a safer tune.

maybe send the pics to black baer?

 

[blackelky]

It's mostly on #7
View attachment 431130

You're right NAPA batteries do suck. Walmart AGM here I come.

 

[Doubeleive]

I'm pretty sure that plug on the left is toast. the special metal, I don't know if you're running platinum or iridium, but whatever was there is gone.

they do have some miles on them, probably best to start over with new set and check on them randomly to get a feeling how the engine is running.


from those I'd say you need higher octane fuel or give up some hp with a safer tune.

maybe send the pics to black baer?

Ya I'm going to reach out to BB dropping it off at the shop today so they can do a deeper dive and see if anything pops up for causing the difference in bank 1 and bank 2 getting new plugs minimum.

 

[Doubeleive]

You're right NAPA batteries do suck. Walmart AGM here I come.

is it giving you problems? that voltage doesn't look bad it's not going to park on 14v all the time, the gmt800's without rvc would but not these trucks, although a "new" battery shouldn't wiggle around as much as a older battery will

 

[blackelky]

is it giving you problems? that voltage doesn't look bad it's not going to park on 14v all the time, the gmt800's without rvc would but not these trucks, although a "new" battery shouldn't wiggle around as much as a older battery will

My last one was always at 15-16

 

[Charlie207]

I really need to get started on my LC9 I bought almost a year ago and haven't touched.
I have no idea if it's healthy or not(supposed to be, pulled from a wrecked Silverado), and I'm still figuring out what all parts I'm going to put in it

And I've had the good luck to notice that I'm getting idle surge/hunting with the AC on now that it's hot enough to require it

I'm as naive about A/C issues as anyone, so no help there....

But, just start tearing the LC9 apart. It's easy to send the block, rotating assembly, and heads to the machine shop to have them inspected. It's either good or it's not, and it's probably good as long as it was never oil-starved. The factory bearings (minus the cam bearings for some reason, per my machinist) are incredibly robust, and the last seven LS engines he's worked over didn't need new main or con-rod bearings. Just slap in some new cam bearings and a set of stock piston rings (he recommended Hastings). Do a little at a time, and in a year you'll have a fresh engine to plop into your car.

 

[Charlie207]

Replaced the power steering pump and reservoir. Replaced the lines recently, hoping that would end the seeping/leaking, but the cast iron pump body seemed to be magically seeping fluid through its pores.

Old:


New:


Ignore the heavy patina on everything else.

 

[89Suburban]

Dayumm haha

 

[Charlie207]

99% of the videos I watched for learning about the removal/install procedure had you spend a bunch of time disconnecting the battery, alternator, and removing the accessory bracket. That seems stupid compared to how much less work it is to just unscrew four 15mm bolts, twist out the PS pump, and disconnect the high-pressure line in plain view, instead of fumbling with the fitting after the pump is reinstalled.