ACDelco GM Original Equipment 10-3015 (19355198) Engine Cylinder/Combustion Chamber Cleaner - 32 oz

Heard about this in forums, as being superior to other top engine treatments. Used it as an overnight top-piston soak, plus as aspirated via vacuum into the intake manifold with engine running. Although initially the post-treatment cylinder compression read 4% lower at first, the engine ran smoother and more quietly, peppier, and the engine monitor readout of mileage went up by 10%. Thus, good signs of effective carbon cleanout. In time, I'll reevaluate the compression and mileage results. Although this is pricier than similar products, it appears to work quite effectively. I'll carry on to keep carbon minimized, such as with use of Top Tier gasolines and synthetic oil.

I've been trying to clean these pistons with brake cleaner, carb cleaner, sea foam, and several other cleaners nothing really worked at all then I took a chance on this and wow did it work great. I poured a small amount onto a paper towel and coated the piston as I did this I could see it start to run off right away gave it a few seconds and bam it wiped off like a nonstick skillet with just a paper towel crazy. I had 2 pistons in the back that were really bad and I had to let it sit on them for a minute or two but bam came clean if you need to clean carbon build up and stains on pistons or engine parts this is worth every penny turned a 2-3 hr cleaning job into a 15 minute job. Don't hesitate just buy it.

This stuff is great. Mixed the whole bottle with 1/2 gallon of diesel and idled the engine until the mixture was used up. Before I ran this through, cylinder #4 was at 14% and there was a heavy visible smoke from the exhaust. Since I ran the the mixture through, I've put several tanks of fuel through the engine and the issue hasn't returned yet. All of the balance rates are +/- 1.5 still. You will need 4 feet of 1/2" and 3/8" fuel line and a hose clamp for each. Also, an inexpensive fuel line release tool is needed. It's worth a shot!

works as designed, fast shipping

I had a mysterious whistling noise coming from the engine compartment on my GMC Yukon Denali. It was quite annoying and would only occur in certain RPM bands. I took it to several mechanics who could not find the cause, and sometimes pointed me to a GM service bulletin that said the whistling is normal because of the way the intake passage is designed. However I knew it was not normal because the car did not do this when it was newer.So I used this engine cleaner, sucking it into the PVC valve vacuum tube at high idle, then let is soak 30 minutes.After this cleaning the whistle noise was gone! I couldn't believe it! I was able to do a home garage fix for something that puzzled every mechanic! Apparently this must have cleaned out carbon deposits that caused the air to get constricted in the intake passages to create the loud whistling noise.I think I might just use this magic stuff every year.

Use this for multiple purposes like cleaning motor parts and doing piston ring soaks. Frees up stuck rings reducing oil consumption and increasing compression. Great stuff

I used this to soak the pistons in my 275k mile 2007 prius overnight and I went from burning 1 quart of oil every 700 miles down to 1 quart over the whole 5000 mile oil change interval!I removed the spark plugs, added about 1/4 cup to each piston, moved it up and down a few times and then let it sit overnight. In the morning I vacuumed the remaining liquid out with a mitivac and a whole bunch of junk came out. The car smoked a bit upon startup, I did some hard driving to really ensure it got worked in and had great success.

Takes it all off…. Good degreaser for unpainted surfaces