BerrymanProducts 2611 Intake Valve and Combustion Chamber Cleaner, 16-Ounce Aerosol

Super simple to use. Followed the directions on the box and had a bunch of carbon burn off. No check engine lights or problems of any kind. Throttle seems more responsive now. My car is a GDI and has 41000 so I may do a second treatment to be sure.

This product is freakin amazing. Ignore the negative reviews, those are people who have no clue. I ran one can through my 2012 Jeep Liberty V6 that was getting 12-16MPG and had poor pedal response and no acceleration. I had put plugs and wires, air filter because we just bought it for my daughter and it had 118k miles on it. We took compression test and it was fine. Narrowed it down to possible carbon buildup. Well CARBON BUILDUP INDEED! This thing smoked during the entire can during idle and almost none when driving. Immediate increase in acceleration. Fuel mileage restored to 15-19MPG, which for 118k miles is good enough! I felt the car had more to give so today (a week after the first can) I ran a second can through. This time it did not smoke during idle, but on the road test it burped quite a bit of smoke and the check engine lite came on and went off. no big deal. I was right, she did have more to give! I got MORE acceleration the 2nd time! At the time of writing this, I did not have the mileage into it to retest the MPG, but I will this weekend. I suspect 16-20MPG now. FREAKIN AMAZING STUFF for under $40! NO brainer!I also ran a can through my son's 2014 Chevy Sonic 4cyl (68k miles) and it did not smoke at idle. During the road test, It was sputtering badly to the point I had to use manual shift to rev up the RPM's. Check engine lite blinking. I stopped, let the engine recover and pulled out onto the main road. It started to accelerate and then almost died. I lost all power momentarily. Then this Hiroshima cloud came out the tailpipe, HOLY CRAP WAS THAT A MASSIVE DENSE CLOUD! Afte that, it cleared up and once again, we got the same results, much better acceleration and a 2.4MPG increase, it now gets 29MPG city! (prior was 26.6MPG).I ordered 2 more cans to run through my 2012 Silverado with 788K and my wife's 2017 wrangler with 50k.These cans are worth the investment, you immediately get it back and then some in recaptured MPG, let alone the better performance factor.

I have a 2016 Mazda CX-5 with a 2.0 SkyActiv-G engine, which uses GDI technology. I currently have a little bit over 138,000 miles. My engine runs fine, but I figured it couldn’t hurt to clean the valves just in case it was gunked up.Instructions are clear and everything is provided in the package. It took approximately 10 minutes of idling to empty the can.After letting it sit for 30 minutes, I went for a drive. Engine ran fine until I decided to floor it on the highway. It stumbled, threw a code, and went into limp mode.The code was for a rich fuel mixture. I suspect some of the product had pooled in the intake manifold, and once I floored it, an excess amount was ingested, causing an overly rich air/fuel mixture. I advise everyone to NOT use full throttle acceleration in order to mitigate the risk of flooding the engine, or worse, hydrolock.Just take it easy and cruise around town. The package recommends 10 minutes of driving post treatment. I’d say go for 30 minutes just to be sure. In fact, I could smell the burn off from the exhaust while driving around town. No white smoke though.The next day I took the car out for some errands and immediately noticed that the engine sounded a little bit different. It felt more responsive, sharper. I would have to remove the intake manifold to confirm the results, but for now, it seems to have had a positive effect.

I would have given this five stars except that there was a leak in the clear plastic hose where it was kinked rather than being gently folded over itself. It wasn't a big deal -- I just cut the hose at the leak and re-attached the fitting -- but it could have been had it gotten into my eyes.In fairness, I should mention that I've never had this happen before. But it was concerning enough that I thought I should mention it, along with a warning to inspect the holes before pressurizing it and immediately upon pressurizing it. If there's a leak, then shut off the valve. The solvent is very strong and could do some damage to an eye.That singular flaw aside, this cleaner works as well as any other I've used. I use it to keep carbon buildup to a minimum on the intake valves and in the combustion chamber of my car's GDI engine.Because the fuel never actually touches the faces of the valves in a GDI engine, you don't get any "fuel wash" effect of the valves; so using a product like this periodically is essential maintenance. It also helps remove carbon buildup around the rings; but the valves are the main targets for products like this.What I like about this particular product is that it can be used without a helper. It's formulated to work with the car running at normal idle speed; it comes with fittings to attach the hose to the engine so you don't have to hold it in place; and the can has a total-release valve that you just have to press down once. The chemical keeps flowing into the intake until the can is empty.In other words, once you attach the hose to the car and depress the actuator, all you have to do is watch it so you can shut down the engine when it's empty. You don't have to hold anything in place or keep holding the actuator down while a helper in the car keeps the RPM's up. You just start the flow and monitor it.I also suspect that the sustained, slow flow does a better job of cleaning than a shorter application. I have no proof of that, however. It just seems sensible that a longer exposure time would work better.If you start using this product when your car is new, you have a good chance of never needing a more-expensive mechanical cleaning or walnut shell cleaning of the valves because you won't give the deposits a chance to build up to the point that they affect performance. If you wait until the deposits are heavy, then this cleaner is still worth trying; but the heavier the deposits, the harder it is for a chemical cleaning to remove them. Better to start early.