STP Ultra 5-in-1 Fuel System Cleaner, 12 oz, Engine Deep Clean, Restore Power & Fuel Economy

This cleaner is legit. I've used it in old Land rover vehicle and it seemed to help with missing a little. I also added a bit to my chainsaw and leaf blower gas (probably double the recommended strength for the volume) and in one tank, both 2 cycle engines were running better as well. All with just one treatment.

I bought a low mileage used truck 2018. Ever since then, it took several cyclings of the ignition to prime the fuel pump before the engine would start easily. I'd tried some other fuel injector cleaners, and replaced the fuel pump (which it needed anyway), with not much change. After the truck was warmed up, it always started right up, and it always ran great when driving. So I had no idea where the problem was, having no obd2 codes. Just this January, I put two bottles of this in my 34 gallon tank. I believe these bottles say they treat up to 26 gallons per bottle, so after I ran the fuel level down a bit, I added about five more gallons of gas so as not to run it overtreated too much. By the time the tank was almost empty, my truck started easily on one turn of the key. Now it starts instantly, faster than any vehicle I've ever owned, new or used. This contains a substantial amount of PEA, according to the sds document I read, and I only wish I'd treated this truck with it the day I bought it. That would've saved me a lot of troubleshooting and efforts to fix an easily remedied problem.

I just started using the product and actually my check engine light came on I'm thinking or hoping that that's a temporary thing as part of the cleaning process for the catalytic converter and the fuel system entirely with those five points of cleaning give it some time before you ask for reviews to get a fair assessment of the products five-part cleaning solutions

My 2014 Dodge Grand Caravan's "check engine" light came on. The computer code was 306, "misfire in cylinder 6." I dumped a bottle of STP fuel injector cleaner in the tank and it looks like that took care of it! Thank the Lord!

I noticed that about three months ago, my older minivan had started running not-so-smoothly anymore. It would randomly start chugging weirdly instead of driving along. I did some online research and they said that ethanol mixed into gasoline can cause a car to develop problems after many years. I wasn't sure how I could clean up my engine? I put in three different fuel treatments, at different times, with no improvement. I got the spark plugs changed -- no improvement. That's when I tried STP Ultra 5-In-1. It's really easy to use -- you just pour it into a gas tank half-full or more (mine was actually on a quarter tank, so I poured in about half.) I was unsure if it would have any impact at all. And yet, to my total surprise, it helped. I haven't had a single chugging incident since. I am really pleasantly surprised. And relieved! So I would suggest if you have issues like mine, you might want to try and use this fuel treatment, preferably BEFORE your car starts running with suspiciously ominous chugging. But even if it already is, this just may be the miracle you're looking for. Really glad I tried this gas treatment!

My car got a burst of energy. I like it.

Vehicle ran better. Kicked out some black from exhaust. Worked well.

Keeps my motor clean and improves my mpg.

When I received the STP Ultra 5-In-1 Fuel System Cleaner, my husband took it out and poured it into the car's gas tank. When I asked him upon returning home from town, how did it do, was there a noticeable difference, he said, IIT did great! Made the engine appear to run smoother. He liked it very well. So, I would say, yes, I recommend this STP Ultra 5-In-1 Fuel System Cleaner.

It's a quality product and I believe it cleans the fuel system well. Only complaint is that the bottle says it is capless filler compatible (or similar words,) but it is not... at least not compatible with a 2017 Jeep Grand Cherokee's capless gas tank. Spilled the liquid all over trying to get it in the filler flap and it wouldn't work (I did get an exchange at my local Walmart and used a funnel.)