STP High Mileage Fuel Injector Cleaner, 5.25 Oz

The first time one bottle in 12 was empty because it leaked out in the carton (no product damage). The second time two bottles leaked and were partially full. Seals should function and caps should be on tighter. Several loose caps in both.
That said, I believe the product is better (more octane boost and has fuel system cleaner) although I have no way to validate that other than subjective evaluation.

I have a 2018 that I’m trying to keep running. Bought these and have been using it for about a year, adding to fill ups once a month. I’m not mechanically inclined enough to tell you if it’s really working, but I’m getting better gas mileage!

It does improve the Octane, I use it with Regular gas now on my BMW X3

order a case but case came broken and fluid all over the case.

Before I let the world know of a great secret that I stumbled on regarding this product, my review of it:

I’ve had fuel injected cars as long as I can remember, and have gone back and forth with whether using high octane gasoline is really worth using, either once in a while, for the “cleaning” effect, or full time for better mileage. I used to be one of those people who did manual gas mileage checks, topping off the gas in the fuel tank, writing down the odometer mileage, then on next fill-up, topping it off at the same pump topped to the same level as previously, writing down the mileage again, and dividing the miles driven (differnce of both mileage points) by the amount of gas in gallons just added to the tank. I used to have fun taking gas mileage readings trying to drive super conservative (speed limit, slow lane only, foot off the gas at the FIRST possible moment when a stop was coming) versus my last tank on super old tires, then again the first time I changed the tires, trying to see for myself what really affects gas mileage.

What I can tell you is this product, although sold as a fuel injector cleaner and carb treatment, does more on the very first bottle to boost gas mileage, than anything I ever tried to do to boost mileage. I have a 2008 Toyota Camry. On the very first bottle of using this, my car was noticeably more responsive with the gas peddle, and I got 5 more MPG. Now that might not be average for the entire tank, but my ’08 Camry has a tank average guage. When I fill it up, it resets both the DTE (Distance To Empty) and the tank average MPG. This product says it treats up to 21 gallon tanks, but I filled my tank to about the 2/3 level only, and dumped in the full bottle of this product. So for my 20 gallon tank, I used one bottle of this when I filled it with about 13 gallons of gas. I wanted to make it a bit more potent than a full tank to see if there is a real difference. I filled to about 2/3, dumped this in, and hit the highway for my 1 hour drive to work. I’ve been doing this on many tank fills before, filling my tank, and jumping on the highway to work, and never saw more than about 33 MPG for what I call “the first hour driving highway on a fresh tank full” – it’s all highway. The first time I dumped this in and drove my hour to work, I saw (and took a photo out of disbelief) 40.1 MPG (not instantaneous, but on the “tank average” – so it kept rising over a 1 hour drive, from about 30 MPG, to 40.1. I was shocked and pleased. I thought I “fixed” (cleaned) my fuel injectors so that I could go another 5 or 10 tankfuls on the benefit of this. I also thought “I paid less than $2 for this, and got another 80 miles per tankful!”. This is a no brainer – this product saves you several fold the dollars in gas you will use compared to it’s price.

Bubble (half) burst: On the next tank of gas, I did not use the treatment, and my mileage plummeted again. I might have gotten 1 more MPG than usual, it was hard to tell, but my fill and drive to work was back to 35 MPG – not 40.1 for that first hour drive with a full tank of gas and this time NOT using this product.

Then I figured – unless this is harmful, I should buy a case of this on Amazon, and use one every tankful, and still save money on gas – not a marginal calculation – but a no brainer definite. So I did.

Needless to say I love this stuff – and am a regular user and proponent of it, and it absolutely saves me money on gas, I get 5-6 more MPG highway, and at least 3 MPG better per tankful – it more than pays for itself every bottle I use, and I don’t seem to be hurting my engine by continued use, so I am hooked.

Now, are you ready for the best kept secret that WILL save you, or someone you tell this to – hundreds of dollars! No, this isn’t an ad – I stumbled across this and hoping this free advice can help others:

I had a Yard Machines leaf and small branch chipper/shredder machine. It is small, paid a few hundred bucks for it, a small gas engine – maybe 5 HP like a minibike engine. After a few years of regular use (here in New England we hammer this machine every year in the fall with branches falling and tons of leaves to shred to cut down by over 50% of the bags needed to bag the leaves for the year), the engine was not running well at all – it basically would start but not stay running, or run so sputtery that it did not have the power to chip the branches or mulch the leaves anymore. Being a small engine, it didn’t even have a gas/air adjustment. I put a new spark plug, and cleaned the AIR filter, but it made no difference at all. I figured the engine was just “tired” and was thinking either buy a new one, or bring it to some small engine repair shop for an overhaul. I thought of this product – and dumped in just a half a shot glass of this product along with filling the tank. Holy Cow! I let the engine idle for just a couple minutes, but immediately the engine “woke up” and ran like BRAND NEW again! My small engine running like BRAND NEW again! I couldn’t believe it. One bottle of this cost only $1.50, and a half a shot per tank in my small engine made it run like new again. What I found was, like my car, that if on the next tankful I STOP using this product, the engine goes back to it’s normal sputtering, so this didn’t “fix” or clean the carb in order to “restore” it to new, I have to use a splash of this product every time I fill the tank.

I can’t explain why this product works wonders on small engines, but it seems as though my small engine probably is in need of a new carb, or a carb rebuild kit, but, using this product has prevented me from retiring the engine, or bringing it in somewhere to get a big bill for a carb rebuild.

Next proof for small engines: My power washer was in its 4th season. Itg got to the point where the engine was gasping (going faster and slower), and no longer had the power to work the power washer at full force – pretty much useless. Again no adjustments, and I once again replaced the spark plug, and cleaned the air filter – and once again it made no difference. I put a half shot glass of this product and filled the tank again, and within MINUTES the power washer was working like BRAND NEW again – with complete full power and smooth running – power washers run at full throttle pretty much all the time.

I wish I had come across this stuff a few years back, when a fried gave me a gas powered weed whacker. I replaced the fuel lines that were old and cracked, replaced the spark plug, that engine DID have a gas/air pair of set screws – for which I went online and played with setting them for days on end, but never could get the thing to run. The best I could get it to do is start up and run until it warmed up, then it would die. The choke was working fine, I just couldn’t place it. I ended up throwing that in the TRASH, rather than bringing it in for service for some carb rebuild, since it was about 15 years old and given to me by a friend as best effort. I just wish I had this stuff to try back then, I am convinced it would have made it run perfectly, as an alternative to thowing it away.

Now one more proof for small engines: I had a chainsaw – which like the weed whacker, was a 2 stroke engine – which means you have to mix the gas and oil together and add to the gas tank – because those super small engines don’t have a separate OIL compartment. In this case, my dad gave me the Sears Craftsman chain saw, which was about 10+ years old, but, had been used only for one season, and looked brand new. It wouldn’t run, and had old cracked gas lines. I replaced the gas lines, but this one would stay running at all – same thing – would start with choke, then choke off to keep it running, but then it would die in 30 secs as soon as it warmed up. In this case, I bought a carb rebuild kit, and that got it running “almost” back to new again. I then used a splash of this product along with the gas/oil mixture into the chainsaw, and it ran like new. I then used it to clean up our last downed trees from a hurricane, and it worked flawlessly. So I can say I have had good luck using this as an additive to small engines, I guess you call it 2-stroke, and 4-stroke engines, with an without a separate oil fill.

I use it on my John Deere 12 year old riding lawn mower, and it still starts and runs perfectly.

I definitely recommend this it not regularly on all of your gas engines (cars, lawn mowers, chainsaws, power washers, everything), and especially if your gas engine is several years old and no longer runs very well – don’t think about a repair or even a spark plug change yet – put a splash of this miracle treatment in, and watch the magic!

PS – I have tried several of the other similar gas treatments – some from STP. This one seems to work even better for gas mileage than the “gas mileage” additive from STP. So they are not all created equal, and this one is a fix-all gem – spread the word. Before you throw away your old gas engine, use this!

Have used this product for many years. Cheapest mechanic you can hire. Cheaper than Walmart. What’s not to like.