STP Direct Injection Fuel Injector Cleaner, Advanced Synthetic Technology Fuel Cleaner Dissolves Hardened Deposits that Accumulate on Injectors, 12 Oz, STP

This stuff works. Turned off my check engine light.

Best investment for old car.

Good product. Worked well in my Direct Injection engine. Would recommend it.

I use this in my 5.4L Ford just to keep the fuel system clean and operational at peak efficiency. So far so good 25 years and over 200K miles. Still going strong.

I bought these to see if they would help my Honda Pilot. I gotta say, I noticed about a 10 % increase in mileage. Nothing scientific here, just more miles on the odometer before I needed gas. Really noticed it on a long trip. Anyway, I think its helping and I've bought them again. My thinking on products like these is this: If your engine is clean -either new or well maintained- you may not notice any significant improvement. Like putting clean dishes in the dish washer. There's no difference but it doesn't mean the dish washer isn't working. If your engine is of average use -like apparently mine was- then this helps clean out whatever unwanted gunk is in there and helps your engine run a little better. If your engine is really bad, then when this stuff cleans it out, well, that gunk has to go somewhere. It gets burned up with the gas and your car may actually run worse until it clears it all out. These are the only scenarios I can think of that would explain why some people swear BY this stuff and others swear AT it! I know its a generalization and of course there are varying degrees of quality and additives from brand to brand, but I think its a pretty fair summary. Also, I add some to my 2 cycle fuel mixes for my string trimmer, snow blower etc. They're not fuel injected but they have all those small ports and needle valves and such that I think products like these can also help keep clean.

Works perfectly for my 2007 Honda Accord and have no issues with my engine. I apply this product once a month and since using I’ve not had my check engine light come back on. Definitely recommend because it’s worth the money and will save you extra money at the mechanic shop.

I purchased a car that had been sitting for a while and noticed some sputtering when accelerating at higher speeds. I ran a bottle of this through with a full tank of gas and by the end of the tank the sputtering was gone!

Greatly improved power in my 2003 car