Fuel system cleaners

[robtt]

I have to use mostly supermarket fuel. Done 7k miles. Read it is worthwhile, every 3k miles ,and in these circumstances , adding STP or Redex fuel system cleaner . Is this true ?

[Nino]

Firstly Redex is crap and tbh I use a fuel system cleaner, but I use Forté its about £15 on ebay and I use that along side V-Power I will only use v-power but thats due to owning an R32.

If you could avoid spermarket fuels, I would recommend it.

[robtt]

Many thanks. Will using one invalidate warranty ?

[cosmos]

I'd be interested to know how many people use premium fuel rather than the cheap supermarket stuff. Never really given it much thought before but would be happy to pay an extra few quid a year if there is a real difference and others have found it worthwhile.

[Brenbo]

I used Tesco Momentum (which I believe is 99 octane).  I have seen a difference between using the Momentum fuel and the regular 95 octane unleaded on previous Civic Type-R's of the same mark.  One I used to fill with 95 octane unleaded after about 3 months from new started to sound raspy and tinny.  The second Type-R same mark and model I filled with Momentum (99 octane) from new as it had just been made available in our area, this car did not develop any of the same noises and lack in performance as its predecessor.  There is also a marginal gain in performance and your engine will feel like it sparks quicker not as sluggish.  Since noticing the difference I will not fill up with anything else other than premium fuels of 97+ octane.  I personally feel it is better for your engine.  In regards to fuel system cleaner, I have never used any in all the years of owning hot hatches.  Neither have I ever felt the need.  Just used premium fuel.   

[Watts]

I just use regular Tesco fuel. The GTI doesn't need high octane unlike the R. I tried Momentum in my old Audi and it did seem to run a bit smoother but the fuel economy was unchanged. Also tried an additive (bought it in Tesco, £3, but not sure which one, possibly Redex, which did improve the fuel economy from 33 to 36mpg on a slow long run) but probably wouldn't bother now. I think my GTI runs just fine as is

[itavaltalainen]

Put in a litre of anhydrous IPA 

[Watts]

I prefer a pint of Fullers Bengal Lancer IPA

[Mk7-GTD]

I prefer gin

[vidman2]

Tesco fuel is no better or worse then Shell or BP, just cheaper, Years ago Redex and its ilk were of use in carburetor engines but can not do much in injection engines, Injector cleaners mightbe  of use in high milage engines but have little effect.

Engines with direct injection dont even allow the cleaning of the inlet valves as the fuel does not flow over the valves.

Not sure what car/engine you have from your post as you have not put that info in your signature - would help in future so people know what motor you are posting about