Unleaded Fuel which one and is expensive worth it!!

[Whites]

Only got the car on Friday and asked salesmen if I should you the higher octane fuel or cheaper,he says use the highest one as its best for the engine and you will get some improvements on MPG , I had a Suzuki before and they was the case,do I use it on the CT

[rich1068]

Possible very slight improvement in fuel economy (stress possible) and probably better for the engine long term more due to the cleaning additives rather than the increased octane rating. Unless you're going to keep it years and do huge mileage I wouldn't bother. 

[talaipwros]

11 minutes ago, Whites said:

Only got the car on Friday and asked salesmen if I should you the higher octane fuel or cheaper,he says use the highest one as its best for the engine and you will get some improvements on MPG , I had a Suzuki before and they was the case,do I use it on the CT

My lexus dealer advised me  to use the cheapest I could find

[Wass]

Lexus have published their minimum recommended octane rating for the CT. It is 87 for all CT models. Using higher octane than 87 means that the ECU has to compensate less for pre-ignition and the engine can run with more ignition advance or possibly a weaker fuel air mixture. Like most computers, it just depends how it happens to be programmed. How it happens to be programmed varies from manufacturer to manufacturer and sometime from model to model of the same car. We already know that the CT ECU can run a number of different options, some of which are driver selected in a very dumbed down manner.

 Supermarket fuel v named brand fuel. All made to the same EU standard and all can come from the same storage tank at the depot. Why do some people say that expensive fuel is better than cheap fuel? The answers to this vary throughout the spectrum from self assurance  to the way their local supermarket looks after its tanks.

[Silversalmon]

I'd go for the premium product, I use Shell V Power in my cars, can't say it's noticeably better, perhaps a 2-3mpg improvement,but i do believe the added detergents are a plus factor in keeping the fuel and engine cleaner,and, in the grand scheme of things, with an average of 50mpg it's not going to break the bank. 

There have been too many reported cases of supermarket fuels causing issues, rightly or wrongly, for me to take the risk. I don't want to get in to a heated discussion, just my tuppenceworth.

[Malc]

..............  always used the cheapest appropriate octane fuel wherever I happen to be ....  and I've successfully covered hundreds of thousands of miles in well serviced and " never miss a beat " running, multiple marque cars over my driving years.

Just my twopenneth'

Malc

[Britprius]

Primarily the amount of power you get from any liquid or gas fuel depends on it's calorific value "the amount of energy it contains for a given quantity", and secondary what the engine was designed to run on. The lower octane fuels contain more calories than the higher octane, and the CT was designed to run on the lower octane rated fuels this is in the handbook. You will gain both performance, and economy by staying with the correct grade.

There is nothing to gain from using higher octane fuels providing there are no problems with the engine such as a faulty knock sensor. If the knock sensor is faulty a higher octane fuel will mask the problem.

John.

[NemesisUK]

There's nothing to loose by using the likes of V Power and possibly gaining a cleaner engine. At approximately £5 extra a tank it's worth it IMHO.

[Britprius]

22 minutes ago, NemesisUK said:

There's nothing to loose by using the likes of V Power and possibly gaining a cleaner engine. At approximately £5 extra a tank it's worth it IMHO.

I must disagree with you there Peter on two counts possibly three.

One your going to get less mpg from V Power in spite of what the adds say.

Two your paying "in your words" possibly £5 extra for less mpg.

A fuel additive "injector cleaner" added twice a year would have the same or better results at less cost.

I did work for Esso Petroleum for a number of years, and most of what you hear is marketing hype.

Although the CT "the car the OP is asking about" has a high theoretical compression ratio, it's actual compression ratio is much lower as being an Atkinson cycle engine the inlet valves are kept open for part of the compression "short compression" stroke so reducing it's compression. It also has a long stroke combustion designed for a long slow burn to get the most from the mixture expansion as it burns. This increases the engine efficiency.

John.

[sorcerer]

Whenever I see topics like this it always makes me smile because it's an argument that just keeps on going - people will believe what they want to believe.

Personally, I think it's all hype. As Wass says above, it's all made to the same EU standard and the one tanker filling up from the one storage tank can deliver to both supermarkets and high-street forecourts on the same day.

MPG is too fickle to make a difference and cannot be proved to be down to the petrol except under laboratory conditions. In the real world it can be affected by many things, even wind speed and direction on any given day, yet some people will swear that it's due to the super-dooper expensive stuff they put in.

If clean engines are your thing (not just the OP but anyone), run on LPG like I do, which is by far the cleanest fuel. 9,000 miles between oil changes and the oil comes out almost as clean as it goes in with no lack of performance - better for the environment, better for the engine and better on the wallet.

[rich1068]

So there we have it OP. The answer to your question. Yes, use it. On the other hand don't.

Now, while we're here I'd like to discuss which are the best cleaning products and whether you should put the new tyres on the front or rear of a front or rear wheel drive car.

[rich1068]

2 minutes ago, sorcerer said:

Whenever I see topics like this it always makes me smile because it's an argument that just keeps on going - people will believe what they want to believe.

You just beat me to it. 

[Silversalmon]

Very interesting point re LPG, I had no idea it was so clean on the engine. Interesting

 

[Rebecca]

I used shell v power religiously for the first few months after purchasing my lexus. I then switched to esso 95 ron and noticed no loss of performance whatsoever. Strange thing is I get slightly more mpg with the regular. 

I stick to regular now but do run the odd tank of v power every now and again to keep the system clean. 

[rayaans]

Not worth it 

The Premium fuels are only really good for high performance vehicles or those that suffer from carbon build up etc.

[Mikeyb999]

I was under the impression it made little difference with an Atkinson cycle engine.  Cant really say I've noticed any difference between brands either.  Mostly use Costco as its cheapest and on the way to / from work, other than that its a toss up between Sainsburys or shell

[rich1068]

My local Waitrose sells Shell so I assume their regular 95 RON is like everyone else's V Power. 

[doog442]

How refreshing that unlike some other forums (BMW) you dont get shot down in flames and told to use the search function as the question has been asked a million times before.

Well done LOC

I've mixed and matched over the years and never noticed a difference (other than in my wallet) so just go with regular. 

 

 

[200h]

save your money just buy a good brand of normal fuel

i have tried it in the past and it made no difference... well except to your pocket at fill up time it cost me more.

on our hybrids we use normal shell fuel.

[peachy]

Only worth buying if your cars been remapped to suit the extra octane or you have a high compression engine such as the is250 and even then it only makes a slight difference to performance. 

For a hybrid your better off saving your money and buying the normal fuel.

[NemesisUK]

55 minutes ago, 200h said:

save your money just buy a good brand of normal fuel

i have tried it in the past and it made no difference... well except to your pocket at fill up time it cost me more.

on our hybrids we use normal shell fuel.

I've used it in the past on my AMG and it made a significant difference on how the engine runs.

Now I use it in my RC300h because it can't do any harm and it may, just may, do some good. It's extra cost is insignificant but it's peace of mind measurable 

[Fatts]

For the last twelve years I have used mostly Asda or Tesco fuels with no problems at all. 

Dont know what you guys are talking about.

[200h]

when i say i've tried it in the past its been on comparable vehicles CT200h and my IS300h and also on our Auris hybrid and its made no difference,

higher octane fuels normally works better with high performance engines.

 

[stormchaser]

I've always used Shell in all my cars. V Power is an expensive waste of time with no effects.

 

 

Sent from my Iphone using Tapatalk

[colin79666]

Tried them all and it made hee haw difference so I now go with whatever I'm passing/is cheapest.  I mostly stick to Asda as I go past on the way to work but will switch to Costco when it opens as long as they are cheaper. 

CTs Atkinson cycle engine doesn't do direct injection so perhaps less benefit from cleaners. 

My previous car (Suzuki Swift Sport) did run better on the 97/99 RON stuff.