But the car is running without issues

Call me crazy but this product made a day and night difference for my 2011 E90 328i Before: rough idle, long cranks, coughy highway pulls, and hard boiled egg exhaust stank. After: peppy, smooth, clean as a whistle. Faster, even.

This isn't a one time use only. It helps reduce carbon build up. Also if paired with an oil catch can

I use this around 1 or 2 fill ups prior to oil changes. Occasionally in between oil changes too. Could just be placebo, but car always feels like it has more pep when this stuff is in the tank. Seems like cheap insurance and good maintenance so I keep using it.

I have been using Jectron for years. Where others injector cleaners fail , Jectron works. I mainly use it on DI Audi engines, where the injectors get fouled up. Jectron will fix rough idles and poor cold starts due to fouled injectors. I no longer will use any other fuel system cleaner.

Works really well, improvements are instantly noticed.

My car loves this stuff as I do, good to run it through the system once a month.

I had some questionable gas from a small town gas station, my FSI engine was idling mildly rough. Place this product in my petrol tank and had noticed increase smoothness. Cannot speak for carbon build up as I did not collect all of the criteria needed to test for this prior to placing it in my petrol tank, however hoping for the best.

I used to use this on my old Grand Prix before I purchased a gti and it worked well in that and still continues to work well in my gti I do this with every oil change just to keep things clean in the fuel system and prevent carbon buildup.

Reduces carbon build up on spark plugs and injectors on turbo direct injection engines. Far superior to most over the counter brands. Less spark plug and coils changes!