I've recently changed to a 1.8 TSi Octavia and wondered if I should use normal (95 RON) or super unleaded (97 / 99 RON). The petrol flap states Super Unleaded / 95 RON minimum and the manual is similarly ambiguous.

My local main dealer says 95 RON should be fine although I remember my old Mk1 vRS used to go better on Tesco's "super" unleaded (99 RON).

Am I right in thinking the new 1.8 engine is FSi ??

I would say use 97 as a norm.

I'm using super unleaded (98/100 RON in my country), but works just fine with normal (95 RON), too. The electronics will take care of it.

Yes, TSI is a turbo charged FSI engine.

thanks for the replies. I used Tesco's super unleaded (99 RON) in my old MK1 vRS so will give that a go.

I did ask the same question of Skoda customer services and was told super unleaded was "higher quality" but either would do!

Da do RON RON RON da do RON RON!

I've recently changed to a 1.8 TSi Octavia and wondered if I should use normal (95 RON) or super unleaded (97 / 99 RON). The petrol flap states Super Unleaded / 95 RON minimum and the manual is similarly ambiguous.

My local main dealer says 95 RON should be fine although I remember my old Mk1 vRS used to go better on Tesco's "super" unleaded (99 RON).

Am I right in thinking the new 1.8 engine is FSi ??

Do you mean the 118kw/250Nm unit with chain drive cams?

There's nothing ambiguous about it - minimum octane rating is 95ron. You can use 92ron in emergencies but it will feel very flat as the timing will be wound back. It's all in the owners manual.

The main difference will be fuel consumption. 95ron gives me 7.4L/100; 98ron gives me 6.6L/100. I drive 90km a day so it costs me near enough the same money to use either (20c difference per day in 98rons favour).

I have no idea what you mean by FSI.

Yes afaik all new VAG turbo petrol engines are FSI i.e. Direct Injection

FSI = Fooking Super Injection

I might have that wrong though!

I'm currently getting 30 mpg urban and 40 mpg motorway according to the OBC. I'll give some of Tesco's finest super unleaded a try at the next fill up.

It is a cracking engine by the way this new 1.8 TSi. I'm still mightily impressed by the low down torque from a little as 2K revs and excellent top end power right up to around 6K revs.

Not missing the old 1.9 TDi one bit !

TSI kicks a ss TDI sucks a ss

TSI kicks a ss TDI sucks a ss

When did this become a Honda forum?:confused:

When did this become a Honda forum?:confused:

just some having some fun!, i did have a honda years ago, great car super engine. But i have seen the Light, Skoda all the way, love petrol the only way to drive

Do you mean the 118kw/250Nm unit with chain drive cams?

There's nothing ambiguous about it - minimum octane rating is 95ron. You can use 92ron in emergencies but it will feel very flat as the timing will be wound back. It's all in the owners manual.

The main difference will be fuel consumption. 95ron gives me 7.4L/100; 98ron gives me 6.6L/100. I drive 90km a day so it costs me near enough the same money to use either (20c difference per day in 98rons favour).

I have no idea what you mean by FSI.

Hi brad : I take it you have tried this objectively "95ron gives me 7.4L/100; 98ron gives me 6.6L/100. "

I see to remember seeing somewhere this engine was set up to run "normally" on 95 Ron so have never tried 98 (or super) Getting an overall average of 38.1mpg over the last 3000 odd miles(according to the OBC) but might try a tank of super if overall you reckon its the same?

Hi brad : I take it you have tried this objectively "95ron gives me 7.4L/100; 98ron gives me 6.6L/100. "

I see to remember seeing somewhere this engine was set up to run "normally" on 95 Ron so have never tried 98 (or super) Getting an overall average of 38.1mpg over the last 3000 odd miles(according to the OBC) but might try a tank of super if overall you reckon its the same?

Mate, I'm somewhat OCD about fuel consumption. I even won a fuel economy competition with Shell a few years back. It wasn't a particularly serious competition but I walked away with AUD5000 and I got 4.5L/100km out of an auto 1.6L MkV Golf (straight out of the showroom).

I would interpret the factory recommendation as being the minimum standard. It doesn't hurt to use a fuel of a better specification - possibly you'll get better power or economy - at worst you'll waste a bit of money.

A lot of cars in Australia come under-specced on the recommended fuel because most Aussies are real tight-arses when it comes to spending money on fuel so the manufacturers detune the ECU maps to run on 92 and you bung 98 in them & it's like you've taken 5 bags of cement out of the boot (or left the Mother-in-Law at home).

Attached is my homemade fuel consumption spreadsheet & graph (in pdf because the forum doesn't seem to accept xls files). As expected, the consumption has reduced as the engine frees up but there appears to be a definite improvement with 98ron.

This is in NSW, Australia so you probably need to know:

• Plus95 contains 10% ethanol (e10).
  
• All petrol sold in NSW contains 2% ethanol but it doesn't have to be labeled as containing ethanol.
  
• Readily available fuels where I live are 92ron, 94ron(e10), 95ron(e10) and 98ron.
  
• Fuel consumption is usually slightly higher with ethanol blend fuels because ethanol is oxygen rich & fools the ECU into squirting a bit more fuel in. Personal testing on previous cars showed the difference with e10 was about 0.3L/100km worse.
  
• Yes, my dealer gave me a free tank of fuel because of a delivery stuff-up and it was only after the event that I found out it was 92ron:mad:. It didn't affect the consumption but it did make the power drop off (and I drove very conservativly for that tank).
  
• My driving is 20% stop/start suburban traffic & 80% motorway (speed limit is 110kmh).
  
• There's a noticeable hit in economy over 100kmh.
  

Skoda Fuel Consumption.pdf

FSI = Fuel Stratified Injection. Its direct injection but the top of the pistons are also moulded to enhance the burn of fuel. It is injected in the form of mist rather than jet.

managed 424 miles on the first tank of 95 RON and is now filled up with Tesco's super unleaded (99 RON). I'll post back next week to let you know if it goes any further / faster.

Cheers Brad, yes I see you're serious keeping details like that. Interesting chart - seems to suggest or even prove there is some noticeable difference. I will try a tank next time here & post my thoughts. Will have to try & find some place selling super at sensible money as there tends to be 5 ~% hike for Super typically in UK.

I find you need to run 2 tanks for the ECU to learn what's going on.

There's about 10c-12c difference (about 7%) between 92 & 98 over here. 95e10 is actually 3c cheaper than straight 92.

The weird thing is that despite fuel going up by 50% over the past 12 months the difference has remained 10c

Take a look at this site:

Mileage Calculator and Vehicle's Costs Analyser