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Discussion Starter #1
I recently rebuilt my 5.3 engine of my 99 truck. Everything was fine during the 1,000 miles of the break-in,then I started to notice some white smoke at times. I changed the pcv and still has the problem. Yesterday I removed the sparks and this is what I found.

20200101_141701.jpg
20200101_141758.jpg


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You have way more problems then just a little smoke.

#3 has some serious issues.

#1,6,2 is ever a bigger mystery. Looks like someone soaked them in leaded gas or farm diesel.

Regardless every plug looks like shit for a fresh rebuild.
 

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Looks like Cylinder 5 is running a tad rich as well. Yes, I know thanks Captain obvious right haha. It could be number of issues honestly. Have you pulled the heads off to see any other under lying issues or just pull the plugs so far?
 

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Toxic Masculinity
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The red plugs look like fuel additives or MMT (octane booster) deposits. The problem is they all should be the same color. With the white smoke, it's probably coolant from a cracked head, bad head gasket or a non flat deck or block surface. Number three looks like severe detonation cracking the porcelain, maybe from a coolant leak situation. You definitely have issues with such nonuniform plug readings.
 

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Discussion Starter #5
Looks like Cylinder 5 is running a tad rich as well. Yes, I know thanks Captain obvious right haha. It could be number of issues honestly. Have you pulled the heads off to see any other under lying issues or just pull the plugs so far?
Just pulled the spark plugs first, i want to do a leak test.
The valve seals are new too.

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Discussion Starter #6
The red plugs look like fuel additives or MMT (octane booster) deposits. The problem is they all should be the same color. With the white smoke, it's probably coolant from a cracked head, bad head gasket or a non flat deck or block surface. Number three looks like severe detonation cracking the porcelain, maybe from a coolant leak situation. You definitely have issues with such nonuniform plug readings.
I put in tank an octane booster cause the tank was full with 6 months old gasoline.
The machine shop did not cut the surface of the block cause they say it wasnt necessary.

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Discussion Starter #7
The truck has only 1,500 miles and runs great , but its smokes a little and i know someting is wrong.

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The truck has only 1,500 miles and runs great , but its smokes a little and i know someting is wrong.

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I'd burn through or empty that tank of gas and see if your problem still exist. Given you added octane booster to old gas and it shows on the plugs you might really not have an issue.

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losing water? pressure test the coolant system with pressure test, with the plugs out, if your pressure drops of, then spin the engine with the plugs out, you will find the cylinder with issue.
 
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