According to the Mk 6 Golf TSi info., it states " Thanks to knock control, unleaded 4 star of at least 95 RON can be used instead of unleaded super plus. In order to achieve maximum fuel consumption benefits on the TSi engine, ultra low sulphur petrol must be used"

Think I have read somewhere that owners (not necessarily of TSi's) found that using the ULSP actually provided less mpg.

Any thoughts? Also which fuel are forum TSi owners using?

You can only buy ULSP in the UK, normal sulphor unleaded is not available here. You have the government to thank when they taxed the non ULSP out of existance a number of years ago.

98 / 100 octane unleaded if possible, but works fine with 95 also.

Don't know about the sulphur stuff.

Shell Vpower giving about 34 MPG (calculated on brim to brim for last 5 fillups) Sainsbury's 95 gave about 32MPG for previous 5 fills.

Find engine has a greater tendency to stall using 95RON

All ULSP, as stated earlier normal sulphur not easy to find

Cheers

Go for Shell VPower or Tesco 99 (super unleaded) by all account they give the best response in the TSI/TFSI engine.

I prefer to use Tesco 99 when passing their door, otherwise all I can get is 97, which seems fine also.

VW state as long as it is 95 RON minimum then that's OK. Personal choice really - but it does deserve the best.

VW state as long as it is 95 RON minimum then that's OK. Personal choice really - but it does deserve the best.

Can't tell a lot of difference between typical 97 and Tesco 99 but as Tesco is handy and a good price I think 'why not?'

No 98 around here that I know of, so can't compare.

Tried 95 and didn't like it at all, though apparently you have to give it several tanks.

Tried 95 and didn't like it at all, though apparently you have to give it several tanks.

And try different suppliers as well to find what your engine likes.

Not all fuel is the same, and every engine will have different preferences. As you say, you'll need at least 2 or 3 tanks of each to form a comparison, which is a lot easier if you do lots of miles.

Tescos 99 seemd to give better performance and better economy to me. As for 95, I use it when I can only reach asda (our asda doesnt do anything over 95) and I do find the engine be a bit rougher. On my last breakdown callout the Audi tech asked what fuel I ran it on and said that Audi (maybe all VAG, he didnt say) had told them to tell their customers to run TFSI engines on 97+ only, no brand in particular, just the higher octane.

I've done almost 20,000km in my 1.8TSI.

95ron gives me fuel consumption around 7.4L/100km (38mpg?)

98ron gives around 6.7L/100km (42mpg) and a bit more low down torque.

So over 100km it costs about 20 cents more to run 98ron. In a year (25,000km) it will cost an extra $50 which is worth it for the better pull.

Oh, and my dealer graciously gave me a free tank of fuel to make up for a misunderstanding. Except they filled it with 92ron. It felt so gutless (I assume the timing was retarded) but economy was still ~7.4L/100.

I've also tried 100ron with 10% ethanol. No difference in torque and fuel consumption was 7.6L/100. Price premium was 20c/L over 98 so definately not worth it.