STP Engine Stop Leak for Petrol & Diesel Engines 300 ml, Improved Concentrated Formula, Conditions your Engine and Prevents Minor Oil Leaks, Mechanical Car Cleaning Products, Made in the UK

This is a good product that helps to clean out the petrol delivery system to your engine. Smoother running, more responsive engine, more mpg. Pour into your fuel tank every 4000miles. Simples! Recommended.

Great product, I was actually just about to re-order it. It helped my car so much, I have a small engine and my car didn't get much maintenance from previous owners - this product did it's job well. Great value for money, cleansed everything I could feel much more power coming out from that engine! Lasted about 4k miles. Highly recommended.

Good quality and good value

Arrived quickly from Amazon, we'll packaged. Put this in a full tank on my 2015 1.2 petrol DS3 w/103k on the clock about 2 weeks ago and so far looks good. My fuel gauge is digital and each quarter is split into 3 blocks, since I bought the car 2 1/2yrs ago I've been gauging fuel use by using the trip computer, trip 1 for each block and trip 2 for full tank, each block was going after about 28 miles, 30 at a push, so each quarter tank gave about 84ish miles, so a full tank was returning about 350 miles, my journeys are very much the same month to month, home-work-home, shopping or popping to MILs. Since I've put this in 2 weeks ago each block in the quarter of the fuel guage has been going off after 35 miles, so 105 per quarter so possibly signifying an increase of 70 miles or so for the full tank.Now in February I did have new tyres all round and a wheel alignment so the new fuel economy could be partly down to that but I have felt that the throttle response does feel much better, I've got this on subscription so planning to put this in my car and the wife's every other month and see how it goes but at first impressions it looks to be doing something positive

I normally fill up with BP Ultimate but on a recent 3,000+ mile road trip knew I would have to fill up with regular 95 for large parts of the trip. I decided to buy the 5-in-1 treatment to mitigate using the regular unleaded, as opposed to thinking my engine specifically needed to be cleaned. For reference my car is a 2022 BMW M135i xDrive and had 16,000 miles prior to the road trip. At around the 2,000 mile mark in my road trip I added the treatment to a tank of regular unleaded. After using the treatment I achieved the best MPG I’ve ever had out of the car, 56.7mpg. Previously my best was around the low 50s. I will now use the treatment every few thousand miles. I am genuinely impressed.

Top ! Best fuel additive i bought in years , compared to other popular brands , it's the best of the best .

I bought some petrol system cleaner for my partner's car and also diesel cleaner for my truck. No problems at all with either vehicle but have they made a positive difference to either vehicle .... the truth is to my eyes and ears, it is impossible to tell if there has been an improvement. All I can say is definitely nothing got worse. Maybe I should have researched more before purchasing?

used this with a full tank of fuel on my suzuki intruder 125 vl lc, for a few days i could tell all the gunk was making it's way through the fuel lines so the bike ran actually worse but once that all made it's way out of the exhaust the bikes runs and sounds much smoother