Help Read my Plugs

$uperstang

$uperstang

Club Member
Last weekend did some WOT blasts and realized she was missing up top at like 5,500 rpms and 100 mph.

So this weekend I put new plugs and wires on and went for a drive.

Problem is resolved and power is back BUT look at my old plugs and tell me what you see:

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looks to me like u could use a bit more fuel, they are a bit too white and ashey

notice how the ceramic and electrode are rounded off, thats getting really hot.

number 1 is kinda scary, looks like somethings burning in that cyl. do a compression test.
 
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#8 is the only one that has a whole bunch of funky looking crud built up on it.

All have a spot of yellow at the bottom of the ground strap just above the threads, looks almost like someone touched them with a highlighter. But #1 ceramic is yellow in color on the back side. You can see this in #3 and #4 they are tan in color and look good but right at the bottom of the strap you can see the yellow. Also #s 5, 6 & 7 you can see the yellow in the same spot.

I have a feeling I know what it is but I want to see if anyone else has the same opinion.
 
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go down a heat range on the plugs. Take out 2 dgerees of timming and leave fuel alone.

Take pics and post back here.
 
Sean said:
go down a heat range on the plugs. Take out 2 dgerees of timming and leave fuel alone.

Take pics and post back here.
Click to expand...

Thanks Sean.

I am going to get one step colder plugs tomorrow and give it a shot without messing with timing first and see what they look like.
 
;1865564 said:
Thanks Sean.

I am going to get one step colder plugs tomorrow and give it a shot without messing with timing first and see what they look like.
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Its about 4-6 overtimmed now looking at the plug. That could be to hot of a heat range and the black oxide and the anti seize screwing with me.

Also get some ngk racing plugs. The cadium makes it easier to read them.

Skip the Antiseize to would ya. Please !!! and clean out the threads with some brake cleaner.
 
One important peice of info I left out was that these plugs have been in the car for 3.5 years. I cleaned them once a year ago.

I never use anti seize so I'm not sure what that shit is. Car has been running like this for 3.5 years tuned with an SCT chip.
 
;1865763 said:
One important peice of info I left out was that these plugs have been in the car for 3.5 years. I cleaned them once a year ago.

I never use anti seize so I'm not sure what that shit is. Car has been running like this for 3.5 years tuned with an SCT chip.
Click to expand...

I take issue with the glazing. Plus the burn mark being up way beyond MBT.

Pop some fresh plugs in and make a hit.
 
ok Same fuel, timing and new plugs same heat range, nothing changed but new plugs:

cyl# 1:
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cyl#7 new plug on the left old on the right:
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cyl#8 new plug on top old plug on bottom:
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There is like a yellow hugh to the strap and like small poweder like particles that are yellowish.

I am thinking I may have some coolant leaking in to each cylinder is where I was going with everything but wanted someone to also come to the same conclusion. The intake was ported and maybe after a few years some stress cracks into the water jackets of the intake causing coolant to come in to the combustion chambers, or am I reading in to this too far?

I guess I'll do a coolant pressure test and see what happens.
 
see where the arrow is pointing. Thats your timming mark. Your way overtimmed or the plug is to hot. See the bluing in the threads just beyond the timiming mark. Thats where the plug is superheating from excessive combustion tempatures near the plug. Its borderline preignition hot.

the slash across the ground strap indicate where you might generally like to see the timing mark in the ground strap.
 

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yeah I think you need a colder plug too, I had a similar issue back in the N/A days. I had to settle on a 2 heat range colder than stock autolite copper plug in order to not detonate on straight 93 octane.
 
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