Waiting for delivery of a new Octavia Elegance Estate 1.8t

THE brouchure says 95 ron for fuel or should I run it on super unleaded 99 ron

Having always ran diesel what sort of real life fuel consumpton do you get from 1.8t?

Did not order a diesel at the time only PD engine available and I now only do low mileage

I think it would benefit from Super Unleaded, just like the 2.0TFSi does. Any turbo petrol car will run better on it. See what the manual and filler cap says when you get it. For example, on the vRS it lists 98RON in large letters and 95 in brackets and smaller text, indicating that 98 would be best, but 95 is suitable.

This revised 1.8T is still quite a new engine for VAG, so consumption figures may not be as available. All depends on your style of driving, length of trip and what sort of traffic and road conditions you encounter. I would say as a rough estimate low 30s round town and upto 40 on a run.

Steve

My post from another thread - except I'm up to 23,000km now.

98ron is definately the sweetspot for fuel. Mine prefers V-Power over BPUltimate, Synergy8000 or Vortex98.

BTW it's a 1.8TSI. 1.8T generally refers to the older 5 valve engine.

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.

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.

I've got a 1.8TSi hatch and it is much better on super - I use Tesco 99, but other's 97 is okay.

You get better mpg than on 95 so much of the cost is offset. You will be amazed at this engine when the revs rise!

An Audi tech who fixed my car on a call out said that the tfsi engines were not meant to have 95 ron petrol, only higher octane. And that they were being told to tell their customers this.

(he wasnt actually promoting any brand, but told him I was running tescos 99 and he said that was good)

Could just be another way to get out of warranty issues tho.

We run our 2.0 FSI on 95ron with no issues, and I ran the Mk1 1.8T on it with no issues either!

An Audi tech who fixed my car on a call out said that the tfsi engines were not meant to have 95 ron petrol, only higher octane.

The 1.8T is designated as a TSI engine and the minimum factory ron requirement on the fuel flap is 95ron. I'd guess you have the 2.0TFSI which has a minimum 98ron requirement.

gadgetman wrote: We run our 2.0 FSI on 95ron with no issues, and I ran the Mk1 1.8T on it with no issues either!

That's great, but neither of these engines are related to the engine that the OP is asking about. He's asking about the 1.8TSI which came out in 2007 (even later in the UK I think).

The 1.8TSI will run fine & with no issues on 95ron but it's even better on 98ron. The choice of fuel will be determined by the difference in price. Down here there's only 6c/L difference (3p?) and the 98ron works out nearly the same cents per km.

You can even run it on standard unleaded (92ron) but it will drop power & torque quite noticeably as it reduces ignition timing & richens the fuel mixture.

I am certainly not an expert on this, was just passing along what I was told, wasnt sure if it applied to the tsi engines

I do have 95 in mine around half the time because of the distance to tescos

I am certainly not an expert on this, was just passing along what I was told, wasnt sure if it applied to the tsi engines

I do have 95 in mine around half the time because of the distance to tescos

If you can't get to Tescos, just use the regular 97 super unleaded from anywhere. (Or 98 if you have it nearby). I'm sure it is better in the TSi than anybody's 95.

I felt that my old 2.0FSi also ran better on super but not such a noticeable difference.

Also, if you keep swapping octanes it takes a while for the electronics to adjust and catch up with what you are using.

My new 1.4TSi is now on its second tank of BP Ultimate,after all it deserves the best.

The instructions recommend 95RON but can also be run on Regular 91RON although it will result in a slight loss in performance. It then states that unlimited use of fuel which has a higher octane can be used but there will be no advantages in terms of engine performance and fuel consumption.

Played this game with my previous 2 litre petrol Golf. I found that running on BP Ultimate or Shell V-Power produced a nicer drive and the fuel economy improved just enough to make it cost neutral compared with running on 95 octane.

It then states that unlimited use of fuel which has a higher octane can be used but there will be no advantages in terms of engine performance and fuel consumption.

I think that my be one of those "lawyers" statements. Mine definately goes better & has better fuel consumption with 98ron.

I'm sure that if it said "will go better on 98ron" some ****** would sue them because their idea of better was different to VWs.

Also, I guess it might depend on where/how you drive. For me it makes a difference and I have the fuel figures to prove it, for others:confused:.

I agree with ednmra about learning the fuel. Even switching from v-power which in AUS is Xron +octane boosters & other additives to BPUlt or MobilSynergy800 (both of which are "true" 98ron fuels) it takes a while for the engine to feel "right".

The 1.8T is designated as a TSI engine and the minimum factory ron requirement on the fuel flap is 95ron. I'd guess you have the 2.0TFSI which has a minimum 98ron requirement.

I run my TFSI on 97+ all the time but on the inside of my petrol flap is says "95RON min, Super Premium Unleaded". Doesn't mention 98 at all.

As of yesterday I'm running the lawnmower on Vpower

I run my TFSI on 97+ all the time but on the inside of my petrol flap is says "95RON min, Super Premium Unleaded". Doesn't mention 98 at all.

As of yesterday I'm running the lawnmower on Vpower

As always differences between countries. 2.0TFSI down here has minimum 98ron on the fuel flap

As always differences between countries. 2.0TFSI down here has minimum 98ron on the fuel flap

I'm sure different countries do tune engines differently according to fuel in use.

E.g. "Super" in USA, at 93, would appear to be lower octane than our ordinary unleaded.

Their regular is about 87. To me all their rental cars, which use regular, feel like they're running on 3 cylinders and using paraffin.

I'm sure different countries do tune engines differently according to fuel in use.

E.g. "Super" in USA, at 93, would appear to be lower octane than our ordinary unleaded.

Their regular is about 87. To me all their rental cars, which use regular, feel like they're running on 3 cylinders and using paraffin.

The Americans use MON (Motor Octane Number) which uses a practical test on a control engine & something else(?:confused:) whereas RON (research octane number) is decided in a less practical manner (wicki it for more info).

Thats correct, Americans do use the MON number and not the RON number. The RON simulates fuel performance under low severity engine operation. The MON simulates more severe operation that might be incurred at high speed or high load and can be as much as 10 points lower than the RON. What you see at the pumps in America is the mean of the RON and the MON (notified as (R+M)/2) So RON 95 in Europe is actaully 89 in America.

Also, to answer the original question posted by Ken Pugh, if your car says use 95 then thats the one to use. The only reason 98 ron exists is due to some cars having a higher compression ratio and they physically have to use 98 to stop pre-detonation. Nothing whatsoever to do with that type of fuel producing more power. Its a myth.

As a note to the above thread, America suffers something that us in England don't have much of a problem with, Altitude. In essence, the higher you go, the less octane rating your engine requires. So you will see in America quite large descripancies in the mean values at the pumps depending at what altitude above sea level you are.

Thats correct, Americans do use the MON number and not the RON number. The RON simulates fuel performance under low severity engine operation. The MON simulates more severe operation that might be incurred at high speed or high load and can be as much as 10 points lower than the RON. What you see at the pumps in America is the mean of the RON and the MON (notified as (R+M)/2) So RON 95 in Europe is actaully 89 in America.

Also, to answer the original question posted by Ken Pugh, if your car says use 95 then thats the one to use. The only reason 98 ron exists is due to some cars having a higher compression ratio and they physically have to use 98 to stop pre-detonation. Nothing whatsoever to do with that type of fuel producing more power. Its a myth.

In the case of BP Ultimate, their advertising spiel states that Ultimate unleaded will provide up to 28 miles further per tankful when compared to "ordinary" fuels. They also state that ordinary fuels can leave sooty deposits in your engine but Ultimate will burn more efficiently and help clean your engine as you drive.

Do you believe all you read?

Are you asking me If I beleive it?

For BP to announce that, I guess it whould be false advertising if it wasn't true. So yes I do beleive it. But, I would imagine it was in a lab test of some sort and it was their fuel against who knows what brand of fuel. Either way, the cost difference between "Normal" BP and "ultimate" BP in the real world, wouldn't amount to 28 miles further. If it did i'd be very surprised.

As you state though, there is one thing going for higher octane fuels. They do seem to add more additives to their "performance" fuels which is why, every few tank fulls of normal derv I fill up with Shells super fuel.

Are you asking me If I beleive it?

For BP to announce that, I guess it whould be false advertising if it wasn't true. So yes I do beleive it. But, I would imagine it was in a lab test of some sort and it was their fuel against who knows what brand of fuel. Either way, the cost difference between "Normal" BP and "ultimate" BP in the real world, wouldn't amount to 28 miles further. If it did i'd be very surprised.

As you state though, there is one thing going for higher octane fuels. They do seem to add more additives to their "performance" fuels which is why, every few tank fulls of normal derv I fill up with Shells super fuel.

BP's claims are not that technical but they must be knackered after 28 miles

He he that would explain alot.

The only reason 98 ron exists is due to some cars having a higher compression ratio and they physically have to use 98 to stop pre-detonation. Nothing whatsoever to do with that type of fuel producing more power. Its a myth.

That is only part of the story.

The fuel injection and ignition systems on modern engines are constantly getting feedback from the engine to allow them to optimise the ignition timing, fuel/air ratio and injection timing. Running a higher octane fuel allows these settings to run in such a way to allow leaner burn and greater ignition advance without pre-ignition. This results in more efficient combustion which gives more power and better fuel economy.

IIRC the Skoda brochure at the time I bought mine gave power figures for the FSi engines all quoted for 98 RON fuel, using 95 RON will still allow the engine to run OK but on reduced output

So in answer to the OP - you don't need super unleaded, but you will get marginally better power output and fuel consumption if you do. Whether it is worth the extra 4-7p per litre is really your personal decision.

The main reason why people see (sometimes) a marginal increse in MPG is due to the "premium" fuel actually being very slightly denser than your normal fuels. As in there is more "actual" fuel in a litre of "premium" than there is in "normal" fuel.

The argument for and against "super fuels" will rage till the day we die I suspect. For every person who says they get more power etc there is a dyno graph disproving what they say. My personal opinion is If it says it in the handbook to use 98, then you should. Although modern cars have knock sensors now so the odd tank of 95 wont do much harm. If it says 95 then use that although using 98 wont damage the car (but will your wallet)

Also, to answer the original question posted by Ken Pugh, if your car says use 95 then thats the one to use. The only reason 98 ron exists is due to some cars having a higher compression ratio and they physically have to use 98 to stop pre-detonation. Nothing whatsoever to do with that type of fuel producing more power. Its a myth.

I can't agree with that. I have 23,000km of fuel consumption records for my 1.8TSI that show 98ron gives better economy than the recomended 95ron. Why does it give better economy? Because I don't have to put my foot down as hard to achieve the same result.

WRT power, it isn't just the calorific value of the fuel that gives power, there is also spark timing, fuel mixture, static CR, dynamic CR, turbo boost, etc.

Down here in AUS most motorists are tightwads so the biggest selling fuel is the cheaper 92ron. Because of this (and supply issues in remote areas) the major players (Ford, Holden, Toyota, Mitsubishi) all tune their engines for 92ron (even the big-banger 6L Vauxhaul they send to the UK is 92ron in AUS) but any enthusiast knows that running 95 or 98 will allow the ECU to adapt to different values of ignition timing & fuel mixture (they run rich standard to stop detonation) which generally gives better performance & economy (some of the owners manuals even state the fact that higher octane fuels will increase performance). You just need to experiment with the fuel to work out which octane best suits the parameters programmed into the ECU.

Of course, if you have a "dumb" ECU and there is no improvement in performance & economy then yeah, you're better off buying a schooner of ale with the extra money.