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

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.

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!

I have a 98 Saturn SL2 that went a long time with a stuck open thermostat valve. I believe this led to rapid sludge and carbon deposits in the cylinder head and piston rings that caused oil consumption to become severe. At its worst, the car was consistently consuming a full quart of oil with each tank of fuel. I added 2 oz. of this product to each cold cylinder and soaked overnight. The remaining thick black solution was expelled by cranking the engine over several times with the spark plugs removed. I reinstalled the same plugs and wires (still fairly new) and drove the car hard to expel all the solvent and loose deposits. Yes, there was a smoke show. I then changed the oil. After driving more than 200 miles, the oil consumption was observed at roughly 1/2" on the dip stick - which is at least half the oil consumption I've come to expect. Furthermore, the fuel economy was measured at 31.5 mpg over my regular commute that saw between 29.5 and 30.0 mpg during the last three years. I also perceive the engine is quieter, shows a bit more power, and has a rock solid stable idle after warm up. Previously, the idle was more erratic. ADDENDUM: I have a better assessment of performance after six weeks. The average fuel economy has been well over 31 mpg with one cycle showing over 32 mpg. The mpg gains are real. More important, the car consumed between 3 and 4 quarts during this period - roughly half the rate of oil consumption before the treatment. So, the reduced oil consumption is real.

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.

I picked up this AC Delco (10-3015) 32oz can as a substitute for the discontinued AC Delco X66P. I used it in my 2011 Duramax 6.6L LML engine hoping to help clean my out of spec injectors. Specifically injector #6. It’s balance rate was way outside the computers specifications throwing an check engine light. I mixed all 32oz into a 1/2 gallon of diesel. The directions on the can clearly state to not put this product in the fuel tank. I hooked up a secondary fuel can with the solution and connected it to my trucks fuel rail. I then started the truck and let it idle until the fuel/cleaner solution was gone. It took about 2 hours for the truck to consume all the solution. Now all 8 of my fuel injectors are back to normal and the truck is running great!

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 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