donjetman
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What did you do to your NNBS GMT900 Tahoe/Yukon Today?
- Thread starter phattyford
- Start date
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hopefully someone else knows better, I think I was confused carbon tracking with peppering. peppering is the specks, which can be conductive and cause a miss, carbon tracking is usually on the oitside part of the plug.
as for the tip, I have no idea what that is. could be iridium that's had a hard life with some ping?
was thinking you might be good at reading plugs from the drag racing days.
any thought on the plugs above? see anything that might cause a misfire?
appears so.......Additionally, on the ceramic there may be specks of material. The two most common types are pepper specks and shiny balls. They show detonation, but the pepper specks also can mean a slight oil-control problem. The specks will attach themselves to the ceramic and the outer shell of the plug. The shiny balls are tiny pieces of aluminum from the top of the piston. Similar to the side electrode, the ceramic also should have a ring around it. This is called the fuel ring. It should be a brown-gray color and half-way up the height of the ceramic. If its too deep on the ceramic, the chamber is again too hot. If its too close to the electrode, the chamber is too cold.
when I get up in the morning I will try swapping plugs 3 & 7 and see what 7 looks like and see if the missfire follows the plug
RooTBeeRthe1st
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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
gooffeyguy
Tom
Yup, what I thought.
You can also use the discolored area on the ground strap and center electrode to determine the correct heat range plug. It's basically how far the plug sticks into the combustion chamber.
4 on the left and 7 on the right, no little ballz on 4 but the inner electrode tip is much shorter
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so could this be caused be a faulty lifter? that's what I am wondering or if it is just detonation, maybe I need a injector balance? I don't know, the fact that doing a crank relearn made a bunch of misfires go away makes me think maybe the crank sensor has been out of wack or needs to be replaced?
Or maybe a intake leak? But the fuel trims do not show it
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
so something is going on creating a imbalance from bank 1 & bank 2
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
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You're right NAPA batteries do suck. Walmart AGM here I come.
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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.
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
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My last one was always at 15-16
Charlie207
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I'm as naive about A/C issues as anyone, so no help there....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
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
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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.
Old:
New:
Ignore the heavy patina on everything else.
Dayumm haha
Charlie207
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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.
