# Best Fuel the TT



## wendigo (Oct 28, 2015)

For my previous cars I never really considered using octane unleaded fuel greater than 91. But for my recently acquired 2.0 litre sport I am seriously considering using 95 octane as I understand performance and economy is better.

So guys what fuel would you recommend ?

Thanks


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## Gren (Jul 25, 2002)

Use 99 myself


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## Edinburra (Aug 19, 2016)

Shell V-Power Nitro+, it contains the best package of detergents which will help keep your engine "Clean" as well as adding to the overall mpg. I never use anything else.


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## Hoggy (May 8, 2002)

Hi, As you mentioned 91 octane I assume you are not in the UK.
98 octane is the minimum if you like to use the performance, but if stuck in commuter traffic day in & day out then use normal unleaded.
Shell V power or 98 octane will always be much better for the engine.
Hoggy.


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## C00P5TT5 (Jul 10, 2016)

Done by the boys at rtech


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## Hoggy (May 8, 2002)

C00P5TT5 said:


> Done by the boys at rtech


Hi, Most people know the ECU doesn't advance the timing immediately, so won't see the true value on a test like this.
Hoggy.


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## C00P5TT5 (Jul 10, 2016)

How long does the ecu take to adjust is it time or milage?


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## Reasty (Feb 6, 2015)

Edinburra said:


> Shell V-Power Nitro+, it contains the best package of detergents which will help keep your engine "Clean" as well as adding to the overall mpg. I never use anything else.


+1


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## Hoggy (May 8, 2002)

C00P5TT5 said:


> How long does the ecu take to adjust is it time or milage?


Hi, Mileage & use through the rev range, & longer if you are mixing 99 with 95 until it is only using all 99 Ron.
VPower + nitro is 99 Ron now.
Hoggy.


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## C00P5TT5 (Jul 10, 2016)

Good to know, cheers hoggy


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## forthay (Feb 23, 2014)

I use Tesco Momentum 99. Seems like a good compromise but I'm sure I'll be corrected by someone in the know


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## Hoggy (May 8, 2002)

forthay said:


> I use Tesco Momentum 99. Seems like a good compromise but I'm sure I'll be corrected by someone in the know


Hi, In 16 years I've not used any but Shell Optimax/Vpower so can't really judge, but from views on here Shell does seem to suit more 1.8T engines than Tesco's.
Hoggy.


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## digital_dreamer (Aug 28, 2011)

forthay said:


> I use Tesco Momentum 99. Seems like a good compromise but I'm sure I'll be corrected by someone in the know


I've used tesco 99 for the last 5 years in the mk 2 TTS and plan do the same in mk 3 ttrs when it turns up.


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## ZephyR2 (Feb 20, 2013)

This has been discussed on here many times before and a search will throw up al lot more info. However -
1.	High octane fuel like V-power @ 98 RON will only benefit engines that are designed to run on high octane. It will not give better mpg or more power to those engines that are designed to run on standard 95 octane. In fact in some cases it can result in less power and poorer mpg.
2.	The standard 2.0 TFSI is NOT designed to run on high octane and you will NOT get better mpg or power from using it. As I recall the TTS engine is designed to use 98 octane and will benefit from using it.
3.	The ECU monitors for pre-ignition or knock and retards the ignition as required if a lower than recommended octane fuel is used. It cannot advance the ignition if a fuel with a higher than recommended octane is used. It doesn't detect fuel quality or octane content it purely monitors for knock. If no knocking is detected then it runs with the normal ignition settings - whether that's with 95 or 99 RON, it makes no difference.
4.	It does take the CPU a couple of tank-fulls to adapt to the change in fuel so any immediate effects noticed are just a placebo effect.
5.	Look inside your filler cap and see what it the recommended fuel for your car and then read page 241 in the manual.
6.	You may obtain some benefits from the claimed detergents in fuels like V-power, unless the same detergents are also actually used in their standard fuels too.


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## EvilTed (Feb 5, 2016)

My short answer. Don't use 91 RON. From memory the 2.0TFSI is designed to use 95 and the TTS 98.

Agree too that using a higher octane than the car is optimised for is fruitless so don't go as far as 98 or 99 with the 2.0 TFSI


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## Omychron (Sep 9, 2016)

ZephyR2 said:


> This has been discussed on here many times before and a search will throw up al lot more info. However -
> 1.	High octane fuel like V-power @ 98 RON will only benefit engines that are designed to run on high octane. It will not give better mpg or more power to those engines that are designed to run on standard 95 octane. In fact in some cases it can result in less power and poorer mpg.
> 2.	The standard 2.0 TFSI is NOT designed to run on high octane and you will NOT get better mpg or power from using it. As I recall the TTS engine is designed to use 98 octane and will benefit from using it.
> 3.	The ECU monitors for pre-ignition or knock and retards the ignition as required if a lower than recommended octane fuel is used. It cannot advance the ignition if a fuel with a higher than recommended octane is used. It doesn't detect fuel quality or octane content it purely monitors for knock. If no knocking is detected then it runs with the normal ignition settings - whether that's with 95 or 99 RON, it makes no difference.
> ...


This. Don't go above the required RON, it gives 0 benefit UNLESS the car is specifically configured to take advantage of it. (Such as the TTS with RON98)

Plenty of people on the interweb will tell you how their car "feels better" with a higher RON, or how their gas mileage improved tremendously on a 20 mile trip!  
None will be able to give you hard facts, or they'll be unable to provide proper proof.

That being said, going below the design octane fuel will force the ECU to adapt, lowering power output.
This also applies to engines remapped to a higher octane rating, off course.


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## wendigo (Oct 28, 2015)

Thank you for your input guys on this subject.

Interestingly and now having looked at page 239 on my Audi TT manual dated May 2017 on this subject it seems Ron 91 is a no no Ron 95 is preferable but Ron 98 is considered the best to use. The manual does not distinguish between any of the engine sizes and outputs so it seems the 98 Ron is ok for a TT , TTS or TT RS.

Fuel for thought.


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## Hoggy (May 8, 2002)

wendigo said:


> Thank you for your input guys on this subject.
> 
> Interestingly and now having looked at page 239 on my Audi TT manual dated May 2017 on this subject it seems Ron 91 is a no no Ron 95 is preferable but Ron 98 is considered the best to use. The manual does not distinguish between any of the engine sizes and outputs so it seems the 98 Ron is ok for a TT , TTS or TT RS.
> 
> Fuel for thought.


Hi, No surprises there then.  
Hoggy.


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## Edinburra (Aug 19, 2016)

wendigo said:


> Thank you for your input guys on this subject.
> 
> Interestingly and now having looked at page 239 on my Audi TT manual dated May 2017 on this subject it seems Ron 91 is a no no Ron 95 is preferable but Ron 98 is considered the best to use. The manual does not distinguish between any of the engine sizes and outputs so it seems the 98 Ron is ok for a TT , TTS or TT RS.
> 
> Fuel for thought.


Way to go.


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## Venom7000 (Jul 23, 2017)

ZephyR2 said:


> This has been discussed on here many times before and a search will throw up al lot more info. However -
> 1.	High octane fuel like V-power @ 98 RON will only benefit engines that are designed to run on high octane. It will not give better mpg or more power to those engines that are designed to run on standard 95 octane. In fact in some cases it can result in less power and poorer mpg.
> 2.	The standard 2.0 TFSI is NOT designed to run on high octane and you will NOT get better mpg or power from using it. As I recall the TTS engine is designed to use 98 octane and will benefit from using it.
> 3.	The ECU monitors for pre-ignition or knock and retards the ignition as required if a lower than recommended octane fuel is used. It cannot advance the ignition if a fuel with a higher than recommended octane is used. It doesn't detect fuel quality or octane content it purely monitors for knock. If no knocking is detected then it runs with the normal ignition settings - whether that's with 95 or 99 RON, it makes no difference.
> ...


I do not wish to question your knowledge but some of this just doesnt seem right.
On my TT 2.0TFSI *fuel cap* and in the *manual* you can read that it *says min RON95*. (implying that it is designed to use higher octane and the minimum is 95)

The user manual specifically suggested that the only times you will experience power loss is when you load lower than 95RON ( I can get a screenshot of that page tomorrow). Having a car use higher RON and lose power makes zero sense. And even Audi gives the green light to use any RON as long as its above 95.
I use 98 and I do genuinely get better milage (I use highways a lot travelling daily between cities).


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## Venom7000 (Jul 23, 2017)

Omychron said:


> This. Don't go above the required RON, it gives 0 benefit UNLESS the car is specifically configured to take advantage of it. (Such as the TTS with RON98)
> 
> Plenty of people on the interweb will tell you how their car "feels better" with a higher RON, or how their gas mileage improved tremendously on a 20 mile trip!
> None will be able to give you hard facts, or they'll be unable to provide proper proof.
> ...


See if there is a way for me to give you the "proper proof" I would (I dont suppose Audi TT main unit can download the trip log on to a USB. That would be nice) 

The fact is that I rarely drive around town. I mostly drive on highways and I do get better milage and range. Just by simply knowing that for a specific trip I need to refuel the car 1 time on 95RON. But on 98RON I don't have to and I still get 30miles (before the engine shuts down) as I park the car in my destination.
So yes I don't have the "hard file log of the fuel consumption" but I do have practical experience from going the same stretch of highway between two cities for easily over 100 times. (results never change)


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## Omychron (Sep 9, 2016)

Venom7000 said:


> See if there is a way for me to give you the "proper proof" I would (I dont suppose Audi TT main unit can download the trip log on to a USB. That would be nice)
> 
> The fact is that I rarely drive around town. I mostly drive on highways and I do get better milage and range. Just by simply knowing that for a specific trip I need to refuel the car 1 time on 95RON. But on 98RON I don't have to and I still get 30miles (before the engine shuts down) as I park the car in my destination.
> So yes I don't have the "hard file log of the fuel consumption" but I do have practical experience from going the same stretch of highway between two cities for easily over 100 times. (results never change)


I tried testing the same, driving 8000km on RON95 and 10000 on RON98.
I use my car for work commute 90% of the time, as we drive my wife's company car whenever we can (free fuel!).
I ended up at 9.4l/100km for both, this is a test over several months.
Then again, my test is as useless as yours. Variables include temperature, wind, inaccuracy in the car's sensors, traffic, differences in fuel (yes, even at the same pump),...

If an engine is not configured to take advantage of RON98, there is 0 difference.
Higher octane prevents knock. If the car doesn't get knock at RON95, there's no use going up.
Octane has NOTHING to do with gas mileage, UNLESS you get knock when using too low octane. (which might be possible at RON91 for example)

This is exactly the kind of comment I was talking about, feel free to believe your real-life 100-trip test, but you're using data which has too many variables.
Feel free to give an explanation why higher octane would improve fuel efficiency, but I don't believe there is one!



Venom7000 said:


> I do not wish to question your knowledge but some of this just doesnt seem right.
> On my TT 2.0TFSI *fuel cap* and in the *manual* you can read that it *says min RON95*. (implying that it is designed to use higher octane and the minimum is 95)
> 
> The user manual specifically suggested that the only times you will experience power loss is when you load lower than 95RON ( I can get a screenshot of that page tomorrow). Having a car use higher RON and lose power makes zero sense. And even Audi gives the green light to use any RON as long as its above 95.
> I use 98 and I do genuinely get better milage (I use highways a lot travelling daily between cities).


That's not what they imply at all!  
Throughout the entire manual the Germans don't imply, they say where it's at. Everything is written this way, to prevent any ambiguous information.
The text on the fuel cap is clear: Minimum RON95, as lower octane hurts fuel efficiency and power output. Want to add more? Feel free, as it won't hurt.

That being said, I've never heard of cars losing power at higher octane fuels, and can't see any reason why they would...


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## Hoggy (May 8, 2002)

Omychron said:


> That being said, I've never heard of cars losing power at higher octane fuels, and can't see any reason why they would...


Hi, If the ECU cannot advance the Ign timing far enough then using 98 Ron could cause a power loss, as the fuel could ignite when the piston is on it's downward stroke causing power loss.
That being said a turbo engine ECU will usually have plenty of scope to advance Ign timing well beyond what may be required.
If an engine is designed for 98+ as most TT engines in the UK are, then use 98+ or there will be a loss of power & efficiency.
Hoggy.


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## ZephyR2 (Feb 20, 2013)

Most Mk3 TT engines are not designed for 98 RON Hoggy only the TTS and possibly the TTRS. The majority are 95 RON. It says so inside the filler cap.

Sent from my iPhone using Tapatalk


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## drjam (Apr 7, 2006)

EvilTed said:


> My short answer. Don't use 91 RON. From memory the 2.0TFSI is designed to use 95 and the TTS 98.


I'm guessing the OP may be in the US? (where their 91 is about the same as our 95).
To add to consumer confusion, UK "premium" or "super" unleaded varies between suppliers. 
Most seem to be 97. As far as I know it's just Shell and Tesco that are 98/99?
(I seem to remember BP sold one that was above 100, but not sure they do anymore).


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## Hoggy (May 8, 2002)

ZephyR2 said:


> Most Mk3 TT engines are not designed for 98 RON Hoggy only the TTS and possibly the TTRS. The majority are 95 RON. It says so inside the filler cap.
> Sent from my iPhone using Tapatalk


Hi, I'm not surprised, if tuned to use 95 it will help keep fuel costs down.
Hoggy.


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## ThePhoenix (Mar 14, 2016)

"The standard 2.0 TFSI is NOT designed to run on high octane and you will NOT get better mpg or power from using it."

I do. Jus sayin.

2 years of every fill-up from all sorts of fuel.


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## Omychron (Sep 9, 2016)

ThePhoenix said:


> "The standard 2.0 TFSI is NOT designed to run on high octane and you will NOT get better mpg or power from using it."
> 
> I do. Jus sayin.
> 
> 2 years of every fill-up from all sorts of fuel.





Omychron said:


> Then again, my test is as useless as yours. Variables include temperature, wind, inaccuracy in the car's sensors, traffic, differences in fuel (yes, even at the same pump),...


Such science. Much accuracy. No variables.


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## FJ1000 (Nov 21, 2015)

Surprised there are so many forum members that haven't remapped their cars! Haha

Remap, utilising the full benefit of ignition advance that 99RON will give you and then you can stop wondering about the fuel as you'll have to use 99! 

Sent from my iPhone using Tapatalk


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## Omychron (Sep 9, 2016)

FJ1000 said:


> Surprised there are so many forum members that haven't remapped their cars! Haha
> 
> Remap, utilising the full benefit of ignition advance that 99RON will give you and then you can stop wondering about the fuel as you'll have to use 99!
> 
> Sent from my iPhone using Tapatalk


Which is what I did.


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## Mark Pred (Feb 1, 2017)

I don't notice any difference putting 95, 98 or 99 in my car. I only tend to put 99 in it as the closest garage to home happens to be a Tesco, else I don't give it a second thought. It's just petrol


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## TT-TDI (Oct 31, 2017)

What about diesel? Does ultimate or Vpower make a difference?


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## Omychron (Sep 9, 2016)

TT-TDI said:


> What about diesel? Does ultimate or Vpower make a difference?


Not for consumption AFAIK. I believe the difference lies mainly in additives?
Whether or not those work is subject for even more debate than octane ratings.


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## ZephyR2 (Feb 20, 2013)

Omychron said:


> Whether or not those work is subject for even more debate than octane ratings.


LOL or should we widen the discussion to whether supermarket petrol is any different to branded.

Sent from my iPhone using Tapatalk


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## wendigo (Oct 28, 2015)

Well this topic has certainly fuelled an interesting debate. For my sins I did use 91 fuel in my previous mk 3 TT and that was supermarket sourced. And the performance was decent and economy good. 
But will take note of the recommendations on the fuel flap and hand book this time and feed my new TT either 95 at least or 98 .
Should certainly fly round the roads in Norfolk a bit quicker than before!!


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## Hoggy (May 8, 2002)

ZephyR2 said:


> should we widen the discussion to whether supermarket petrol is any different to branded.


Hi, Please No, it's getting more like FaceBook on here every day. :? 
Hoggy.


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## Edinburra (Aug 19, 2016)

wendigo said:


> Well this topic has certainly fuelled an interesting debate. For my sins I did use 91 fuel in my previous mk 3 TT and that was supermarket sourced. And the performance was decent and economy good.
> But will take note of the recommendations on the fuel flap and hand book this time and feed my new TT either 95 at least or 98 .
> Should certainly fly round the roads in Norfolk a bit quicker than before!!


Yes I've noticed that this topic has some fairly *pumped up* and some comments are pretty *high octane* whole others *gas* is at a peep. :lol: :lol: :lol:


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## ThePhoenix (Mar 14, 2016)

Omychron said:


> ThePhoenix said:
> 
> 
> > "The standard 2.0 TFSI is NOT designed to run on high octane and you will NOT get better mpg or power from using it."
> ...


Yes I appreciate the lack of controls and it worried me too, but I now have convinced myself despite of the lack of pure science in my recording, measurable efficiencies exist with the use higher octane fuels. Here is my reasoning:

I agree completely with you that these MPG figures are clouded by all of the uncollected and unknown values for temperature; road friction; tyre pressure; inclines; wind speed; and whatever else exists that can skew the results. These things having a significant effect and over the 36,000 miles of test results, one would expect a non-effect of higher octane usage to be averaged out and 'lost', but a relationship between higher octane usage and better MPG always shows.

Attached are my figures, broken down and graphed in 6-month chunks; higher octane than 95 wins every time. If this engine is not running more efficiently on higher octane fuels I would strongly suggest that these results would not be seen.

So, for me the strategy is clear. I seem to get about 4.5% better efficiency from 97 octane fuel over 95, at an increased cost of about 3%. Even with poor tolerances, I'm no worse off and probably a little better off. Tesco 99 octane is competitively priced, so if I am there and needing fuel, I buy that, as my figures suggest that that is an even better bet.

All said and done, I am happy and it will take someone with better stats than mine to convince me that this engine doesn't re-tune to take advantage of fuels up to 98/99 octane.

I'm not too fussed about all this, but as I have the numbers I thought I'd share.

As the Americans say YMMV.


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