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Discussion Starter #1
After noticing a decent amount of carbon build up on top of my pistons last time I changed my spark plugs, and the car definitely feeling a bit more sluggish than it used to, Id like to ahead and try a few "treatments" to see if they make any difference at all. I ordered a borescope and am looking to do before and after shots each time. (I use quality gas and have done regular oil changed with full synthetic, but I guess that only carried me so far. Also my throttle body is clean and I cleaned/oiled my CAI as well.)

Ill be spreading these out a little since I dont want to have to worry about changing oil or spark plugs afterward, so well see how it goes as I work my way through them.

Some products I already have are: Seafoam spray, mopar combustion chamber cleaner, AC Delco injector/upper engine cleaner, as well as fuel tank treatments like Techron complete and redline SI-1. If theres others youd like me to test, feel free to mention it. I tried to stick to fuel additives with PEA since that seems to be recommended for breaking down carbon.

An oddball id like to try as well is the old school water decarbonization, but figured id look on this site for any info on that before doing it.

Anyways, any recommendations for this project? I looked into removing the spark plugs and fuel pump fuse(s) so I can let the stuff sit on top of the cylinders and then turn over the engine to remove whatever I can, but I feel like it would be difficult to get all that liquid out with the engine positioned as it is. Any tips for that or should I not bother?
 

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Personally, I would do a standard Seafoam treatment through the intake. I've never had to change plugs afterward.

Also, I try and run Marvel Mystery Oil in a tank of premium fuel every once in a while. Who knows if it works, but I've never had a problem with it.
 

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Hell, marvel mystery oil is good stuff. I use it on a lot of things, its even pulled surface rust off of an old shotgun of mine.
 

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Discussion Starter #4
So I decided to start with the old school water decarbonization. I used a small red stirrer straw to suck up the water in small amounts and had someone help keep the rpms up. I only ran maybe a cup or so of desalinated water through it, but it most definitely had an effect on the carbon build up. The top of the pistons have much more bare metal showing and the walls were cleaned up a little, although theyre still more on there.

Im what some people refer to as a "complete idiot" and managed to delete the original videos showing how bad it was at the start, but here are my four combustion chambers as they sit after the water treatment. I took the spark plugs back out and they were totally clean still.

I know the build up on top of the pistons probably isnt having much of an effect, but what about the stuff stuck to the walls?

Going from passenger side to driver:
(1)
https://youtu.be/SnbwtCsac4Q

(2)
https://youtu.be/CALxDuwXLRk

(3)
https://youtu.be/9blN9EzV-VI

(4)
https://youtu.be/3z1qEin2_7o

---------- Post added at 11:54 AM ---------- Previous post was at 11:53 AM ----------

Next Im going to do mopar combustion chamber cleaner. I need to change my oil fairly soon, ill likely do it when Ill have time to do both.
 

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Discussion Starter #5
So I ran a full bottle of the mopar combustion chamber cleaner through it. Very similar process as seafoam though the vacuum line as well as directly through the 12 oclock position on the throttle plate.

I let it soak for about a half hour instead of the 5-10 recommended minutes. It started rough, but maintained idle after a few seconds. After a couple minutes at idle I went out and drove it pretty hard.

I got a misfire CEL and it ran awful for a few seconds, but that cleared up and things evened out.

I wont post the videos, but the results were disappointing. To be honest it almost looked like the cylinder heads had gotten worse. Also, it now seems like its "dieseling" where it stays running for a few seconds after the ignition is turned off. I replaced the spark plugs even though they didnt seem fouled by the process as well.
 
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