STP Diesel High Milage Injector Cleaner 200 ml, Cleans and Protects your Engine for 300 miles, Enhances Fuel Economy, Mechanical Car Cleaning Products, Concentrated Cleaning Formula, Made in the UK

Very good quality value for money easy to use

I'm usually dubious about these type of products as they seem to be a hit or a miss. My van was a little grumpy on startup and noisy to drive but after using this it seems to have restored a little bit of power and the engine is running smoother and quieter than before. It obviously helped clean up some gunk and residue in the injectors.

STO products are very good and do the job depending on how old your vehicle is and how clogged your injectors are. Over 100,000 miles on my car and so far one injector replaced. This product does smooth out the idling and improves performance if used regularly as advised by the manufacturer.

Within 10 miles i suddenly started feeling the car was driving smoother, it was amazing how in cold morning starts it started immediately when i turn the key, no jerkiness due to it being cold.Then i went on a 100-mile trip the day after I put it in the tank, and my MPG exploded, i even had a game with the kids to see if i could get it higher, while keeping up with traffic, and reached 54 MPG at one point but, that was with a bit of neutral on long hills, not much mind you, there was a lot of stop starting as well.After a few days of normal driving I now am running at 48mpg, it is something i have never experienced in my car since I bought it 7 years ago, it has constantly been running at around 28mpg , 2007 ,model ford galaxy 2.0tdci. For those that use km a liter that is around 18km per literI think if this lasts a while, i am going to put in a bottle every third tank of fuel.

Magic stuff. I'm dubious of products like this because I know cars need looking after properly and there's no magic wand.I have an old diesel that's fast approaching 150k. It was running rough, down on power and idling all over.I thought I'd try this pre a service. Put it in with a full tank and honestly forgot I had. After about 50 miles it's back to normal. Beautiful idling, power back.I've decided to use this with every full tank going forward it's magic.

Cleaned my old diesel right out, great. Genuinely improved mpg which surprised me

Ok

I've been using this in my car for 9 months now and cannot say I notice any difference. It might run slightly smoother but no difference in MPG or build up of carbon in the EGR valve. Still struggled to pass the emissions test too. So disappointed with the results od a long term test.