White powder/crystals on spark plug electrodes

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Good evening and greetings to all in the land of the Great and Awesome Bitog!

So, as some of you might have gathered, I've been a working on "Thunder the Wonder Pig." She's a 1995 Oldsmobile Cutlass Ciera with the 3.1 V-6.

This morning I changed the spark plugs, (finally). All of the plugs had a white crystal/powder on the electrodes. One in particular, (on the front bank), had quite a build up of this stuff, to the point the gap was almost filled and the electrode was caked up pretty good with this substance.

I've never seen anything like this before, (usually, the plugs I pull are oily and have a carbon coating).

What are these white crystal things? I be curious.
 
Originally Posted By: Falken
Maybe you are burning coolant?


That's what I was afraid of. I'm thinking I might need to add another pack of Walnut dust.
 
Originally Posted By: Falken
Smell it and see if it smells like burnt sugar


Smelling plug now . . . . . It smells like oil.

I crushed some of the white powder with my thumb nail and it does kinda smell like caramel . . . . maybe, but then maybe that's just me. If it is there, it's not a strong smell.
 
Not my plug - but mine looks just like this one

x5trae.jpg
 
Does your oil look normal? If it looks chocolatey it is a HG.

But you can blow the HG just beside the combustion chamber and it won't get into the crankcase.

Wait till engine cools and top up the coolant and see if a fast idle will make it spill or if you see bubbles.

Or you can do a hydrocarbon test of the coolant, or do a pressure test.
 
Originally Posted By: GreeCguy
Not my plug - but mine looks just like this one

x5trae.jpg

That's additive residue from oil burning. I've seen the same thing on the side of a cylinder head from a leaking valve cover gasket. M1 leaves a lot of residue....

Wayne
 
Originally Posted By: Falken
Does your oil look normal? If it looks chocolatey it is a HG.

But you can blow the HG just beside the combustion chamber and it won't get into the crankcase.

Wait till engine cools and top up the coolant and see if a fast idle will make it spill or if you see bubbles.

Or you can do a hydrocarbon test of the coolant, or do a pressure test.


Oil is not milky, nor is there oil in the coolant. I know these motors are prone to intake gasket leaks and I'm somewhat fearful that this is the beginning of said leak. Coolant does "disappear" but at this point, it's very slow, (top up every now and then).

She does use oil. I've been running a 15W40 and changed it yesterday to a straight 40W, (simply because I had a box I bought on sale a few years back and thought I'd give it a try). When I pulled the plugs, I fully expected them to be at least somewhat fouled because it's been burning some oil, but I thought I'd find the plugs black with oil and carbon - never seen the white stuff.

She's running better, but still not 100 percent. Plenty of power under full throttle, but normal gas pedal at a stop light sometimes she still bogs and hesitates a little.

So far, I've changed fuel filter, air filter, spark plugs, EGR valve, cleaned the PCV valve and cleaned the throttle body. With each thing, she runs better, but like I say, still not 100 percent.
 
Originally Posted By: The_Eric
Did you clean the MAF sensor?


No. When I cleaned the Throttle body, I made a point of staying away from the MAF sensor. I was afraid the stuff I was using might damage it in some form or fashion. Can it be cleaned?
 
Yesterday, I threw in a bottle of Techron in the fuel tank. I used the super concentrate for up to 20 gallons, (I had three quarters of a tank of fuel - so I figure that was about 12 gallons). Drove around yesterday and today after Church. Hit full throttle on the highway a few times. She seems to be improving. A few times at wide open throttle, she jumped like a scalded dawg.
 
If you can live with it burning oil causing the ash, Techron is good.

But if you have a hand pump pressure tester laying around I'd hook it up to your radiator if you have the proper cap adapter.

Just knowing your HG is fine is worth it.
 
Is the white residue hard, almost like concrete?

I had that problem on a '94 GMC 4.3L v6. Grayish-white residue buildup on one of the spark plugs, to the point that it would begin to fill the gap between the electrodes. I was advised that it was probably a defective valve guide that was slowly but consistently leaking oil into that cylinder. The oil would burn off, but the additives were left behind to build up within the cylinder. (That engine did burn about a quart between oil changes - apparently all within that one cylinder ; ) It never presented a problem as long as I changed the plugs every so often. I wasn't sure whether the residue was conductive, so in order to avoid misfires I used Bosch Platinum plugs (the ones with the center platinum electrode buried within/flush with the ceramic insulator). I would get buildup that bridged the gap between the base of the ground electrode and the ceramic insulator (near the threads), but I never let it build up all the way to the tip of the ground electrode, so I never had a misfire problem.
 
My Corolla burns horrific amounts of oil and every few months I pull the plugs and they look the same as in the picture. Hard white deposits, almost bridging the gap. Clean them, gap them, throw them back in... After the 2nd or 3rd cleaning I replace them.
 
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