Car Hesitant- I Fueled Up With Super Unleaded/99RON

[davidif]

I have run the Auris 1.2T on ordinary unleaded/95RON since purchasing it a couple of months ago I wanted to try Super as an experiment so at the end of last week I ran the tank very low and filled up at Tesco with their 99RON.

The car feels if anything more sluggish and even hesitant which is not what I was expecting. I have done around 100 miles since of mixed Motorway, A road and urban etc. and am slightly puzzled. I wasn't expecting to feel a night & day difference although thought perhaps that it may feel ever so slightly peppier and maybe show an indicated 1-2mpg improvement and what I seem to be experiencing is the total opposite??

On current form I expect to return to 95RON when I have emptied this tank although do I need to give it longer?

[furtula]

Car was made for 95 octane gas. You don't really get more if using octane gas, money wise.

Other uses have reported similar problems, so just stick to 95 RON.

If you want a peppier car, maybe check into tools that give you better throttle response, i think i read people here using PedalBox,  and saying good things about it.

[davidif]

My thought process was that engine is turbocharged and that the electronics would (eventually) advance timing etc.

 

[FROSTYBALLS]

38 minutes ago, furtula said:

Car was made for 95 octane gas.

Not quite - Toyota actually say "Research Octane Number 95 or higher". Which in effect is just a minimum standard.

We've run our cars on 95 or 98/99RON for years pre E10 and felt they ran better in terms of smoothness. Since E10 was introduced, they have been run almost exclusively on Super Unleaded.

Another advantage of Tesco Momentum (99RON) is the better additive package over both versions of 95 (E5 and E10).

Not interested in claims of better economy.

[TonyHSD]

The problem is the quality of the fuel that you have filled up exactly and to everyone surprise every fill up from the same garage and the same pump can deliver slightly different quality petrol.
I noticed that long ago and even one of my worst fuel experiences was with 99 from texaco garage, the car was almost impossible to go, engine was continuing  to work after you turn off the key, it was knocking and the whole experience was surreal. 
My suggestion is add some petrol additive like redex or wynns for cleaning the injectors  and once you use half off the  tank fill up again at different place. 

I have been using Tesco momentum from local garage since last September and the car had noticeably improvement in performance and overall drivability., however using same 99 E5 from another Tesco was not good at all, and from time to time even from my favourite Tesco the petrol it’s not ok, I can feel the car. Same also happens and from other garages, I don’t know why. Currently using E10 95 from BP and adding redex every second refill, the car drives fine but not as good as when on E5 99. 
Redex Petrol Fuel System Cleaner 250ml https://www.amazon.co.uk/dp/B001QLX0UO/ref=cm_sw_r_cp_api_i_0ATY01K0VAZRYQ13YJG8

Wynns 55964 325ml Injector Cleaner Petrol https://www.amazon.co.uk/dp/B004RP3AEM/ref=cm_sw_r_cp_api_i_HSTJ3YAQNQ8K3YDKZ0K4
 

any of these will help you with immediate effect 👍✅

[davidif]

15 minutes ago, TonyHSD said:

The problem is the quality of the fuel that you have filled up exactly and to everyone surprise every fill up from the same garage and the same pump can deliver slightly different quality petrol.
I noticed that long ago and even one of my worst fuel experiences was with 99 from texaco garage, the car was almost impossible to go, engine was continuing  to work after you turn off the key, it was knocking and the whole experience was surreal. 
My suggestion is add some petrol additive like redex or wynns for cleaning the injectors  and once you use half off the  tank fill up again at different place. 

I have been using Tesco momentum from local garage since last September and the car had noticeably improvement in performance and overall drivability., however using same 99 E5 from another Tesco was not good at all, and from time to time even from my favourite Tesco the petrol it’s not ok, I can feel the car. Same also happens and from other garages, I don’t know why. Currently using E10 95 from BP and adding redex every second refill, the car drives fine but not as good as when on E5 99. 
Redex Petrol Fuel System Cleaner 250ml https://www.amazon.co.uk/dp/B001QLX0UO/ref=cm_sw_r_cp_api_i_0ATY01K0VAZRYQ13YJG8

Wynns 55964 325ml Injector Cleaner Petrol https://www.amazon.co.uk/dp/B004RP3AEM/ref=cm_sw_r_cp_api_i_HSTJ3YAQNQ8K3YDKZ0K4
 

any of these will help you with immediate effect 👍✅

I did wonder as to whether I had just got a poor batch of fuel, I have another Tesco not too far away so I will run it down to below half and try again at the other filling station.

In the meantime I'll get some additive to see if I can get it running like its usual self.

 

 

[TonyHSD]

24 minutes ago, davidif said:

I did wonder as to whether I had just got a poor batch of fuel, I have another Tesco not too far away so I will run it down to below half and try again at the other filling station.

In the meantime I'll get some additive to see if I can get it running like its usual self.

Definitely, I have been using Tesco 99 E5 exclusively for 4 months prior to my 200k miles service and when I took the spark plugs out they had the best appearance from all previous times, I believe it’s down to the fuel. 👌

[WazWii]

On 4/4/2022 at 10:44 AM, TonyHSD said:

My suggestion is add some petrol additive like redex or wynns for cleaning the injectors  and once you use half off the  tank fill up again at different place. 

Currently using E10 95 from BP and adding redex every second refill, the car drives fine but not as good as when on E5 99. 
Redex Petrol Fuel System Cleaner 250ml https://www.amazon.co.uk/dp/B001QLX0UO/ref=cm_sw_r_cp_api_i_0ATY01K0VAZRYQ13YJG8

Wynns 55964 325ml Injector Cleaner Petrol https://www.amazon.co.uk/dp/B004RP3AEM/ref=cm_sw_r_cp_api_i_HSTJ3YAQNQ8K3YDKZ0K4
 

any of these will help you with immediate effect 👍✅

If I use the Shell V-Power 99 RON on all occasions from now on as I fill up my TOYOTA AYGO do I still need the Redex and Wynns?

[TonyHSD]

8 hours ago, WazWii said:

If I use the Shell V-Power 99 RON on all occasions from now on as I fill up my TOYOTA AYGO do I still need the Redex and Wynns?

Hi, 

redex usually works to improve the quality of the fuel and if you are using e5 99 Shell or from anywhere else you don’t need to add redex.
Some Wynns addictive usually has better cleaning properties and can be used with any petrol as problem solving solution, for example if your engine is running rough, has high emissions levels or pulsating and lack of power , wynns has been proven to help, not always but they do. Basically if you go for 99 v power most of the time you don’t need any additives. But if only once in a while then you can still use additives especially when you have e10 95 in the tank. 

[AisinW]

E10 is about 5% ethanol amd E5 is 2.5% or less. At least in UK. The detergent PEA amount depends on which gas brand. Shell, BP, Aral, Total, Texaco, Esso, Mobil, Chevron are generally have decent detergent. 2-3x more than mininum. 

We have top tiers fuel gas stations in USA. But in Europe, this top tiers thing not that clear.  

[Trewithy]

Years ago in the USA there was great competition to provide the cheapest gas and one way of making it cheaper was to leave out the additives.  some of the major motor manufactures recognised that this was leading to fouled fuel injectors and other problems so they got together and devised a specification for cleaner fuels with detergent additives calling it Top Tier.  In Europe the quality of fuel was better with the standard being specified by the European Union.

In Europe and the UK higher octane fuels, 98 or 99 octane, are advertised as containing higher quality or greater amounts of additives in order to justify the higher price.  European 98 octane is the equivalent of USA 93 AKI, European standard fuel is 95 octane, which is the lowest available, and is equivalent to USA 91 AKI. 

[Cyker]

In the UK all fuel has a minimum standard it has adhere to to be legally sold; If an engine is built that has trouble with that fuel, it shouldn't be homologated for this country.

Sure using higher-tier fuels should have some benefits, but for any engine to develop problems in less than 10 years from running on normal standard fuel would, to me, be an engine not fit for purpose.

 

[AisinW]

I feel no difference using Super 95 or Shell V power or Aral Ultimate 102.   But I really feel the my pocket is so much lighter.   We use standard 95 RON or 91 AKI (USA), meanwhile Auris Hybrid or Prius 3 are actually designed to run fine on E10 with minimum octane 87 (AKI) or 91 RON. Unfortunately, we cannot find anymore Gasoline 91 RON in Europe.  Lower octane means easier to be burned = cleaner too as long as it does not know or pinging.   I am not sure if the ECU and compression is programmed differently between Prius 3 in Europe and USA. Both are made in Japan though. 

My Prius 04 pinging at light load regardless which Octane I used. Regular, mid to premium, no difference.  Only if I use Marine Fuel with no ethanol, the pinging goes away.  The E10 somehow is truly 10% ethanol in USA. In Europe, it is usually less than 6% and probably it is just enough not to have any pinging from lean burned. 

[WazWii]

On 6/16/2023 at 7:01 AM, TonyHSD said:

Hi, 

redex usually works to improve the quality of the fuel and if you are using e5 99 shell or from anywhere else you don’t need to add redex.
Some Wynns addictive usually has better cleaning properties and can be used with any petrol as problem solving solution, for example if your engine is running rough, has high emissions levels or pulsating and lack of power , wynns has been proven to help, not always but they do. Basically if you go for 99 v power most of the time you don’t need any additives. But if only once in a while then you can still use additives especially when you have e10 95 in the tank. 

Thanks for that. Yes I plan on using Shell V-Power RON 99 from now on at all times.

However the following Wynn's additive would prove useful yes as it is not related to the fuel type/quality?;

https://www.amazon.co.uk/gp/product/B01M04LOK3/ref=ox_sc_saved_title_4?smid=A2CVNMBRHGWYGU&psc=1

Can these damage an engine? I want to clean the injectors, fuel and oxygen sensors plus the maf if the second-gen Aygo has one. I think it does. The throttle bodies, MAP sensors, PCV valves also need cleaning. Not sure the above Wynn's product can do all this as some of these things need individually cleaning. There are some Youtube videos showing how to do this but I wonder if my official TOYOTA licensed dealer can do this for a fee. 

The job/cleaning needs to be treated with care and the correct procedures/cleaning agents used. If done correctly the engine will run a lot smoother. Something to consider.

 

 

[TonyHSD]

4 hours ago, WazWii said:

Thanks for that. Yes I plan on using Shell V-Power RON 99 from now on at all times.

However the following Wynn's additive would prove useful yes as it is not related to the fuel type/quality?;

https://www.amazon.co.uk/gp/product/B01M04LOK3/ref=ox_sc_saved_title_4?smid=A2CVNMBRHGWYGU&psc=1

Can these damage an engine? I want to clean the injectors, fuel and oxygen sensors plus the maf if the second-gen Aygo has one. I think it does. The throttle bodies, MAP sensors, PCV valves also need cleaning. Not sure the above Wynn's product can do all this as some of these things need individually cleaning. There are some Youtube videos showing how to do this but I wonder if my official TOYOTA licensed dealer can do this for a fee. 

The job/cleaning needs to be treated with care and the correct procedures/cleaning agents used. If done correctly the engine will run a lot smoother. Something to consider.

 

 

Hi, this wynns additive it’s very good. No risk damage the engine or anything else. I used twice successfully. Add in the tank of max 30ltr of fuel. Follow the instructions. Take the car on longer run on motorway afterwards, 30-40min constant high speed 60mph or above and few quick accelerations full power. The pcv is best to be replaced, not cleaned. The other sensors and throttle body require manual cleaning, any dealer or car garage, mechanic can do. I have done many times and always a good results. 

[WazWii]

5 hours ago, TonyHSD said:

Hi, this wynns additive it’s very good. No risk damage the engine or anything else. I used twice successfully. Add in the tank of max 30ltr of fuel. Follow the instructions. Take the car on longer run on motorway afterwards, 30-40min constant high speed 60mph or above and few quick accelerations full power. The pcv is best to be replaced, not cleaned. The other sensors and throttle body require manual cleaning, any dealer or car garage, mechanic can do. I have done many times and always a good results. 

Thanks for this. If I get the work done by my local dealer do I need the Wynn's? I assume the oxygen sensors can be manually cleaned by the dealer? So leave it to them?

[TonyHSD]

1 hour ago, WazWii said:

Thanks for this. If I get the work done by my local dealer do I need the Wynn's? I assume the oxygen sensors can be manually cleaned by the dealer? So leave it to them?

Oxygen sensor dealer can not clean and they will likely say no.
Oxygen sensors are only replacement parts when necessary, cleaning its possible but they need to be removed and it’s a laboratory intensive and I am not sure if it will be effective at all.
Does your car gives you any trouble or you just want to do all these cleaning as periodic maintenance? 
If there are no trouble just leave it and only do the regular service.
No need any cleaning procedure like egr on the hybrids for example.  
As people says if it’s not broken don’t fix it.  
The wynns additive simply has chemicals that will rise temperature and burn the soot if there is any  accumulated along the exhaust system, you can add if you have issues or as periodic maintenance once in a while. Also these additives content some cleaning agent that may help you with injectors and fuel system., but again if you have rough idle , higher emissions, pulsating or vibrations under heavy acceleration, something to make it worth a try. 👍

[WazWii]

5 hours ago, TonyHSD said:

Does your car gives you any trouble or you just want to do all these cleaning as periodic maintenance? 

As the car has reached the mid-life-cycle stage I thought cleaning would be a good idea to preserve it for longer. 

I think there is a minor problem. Sometimes upon start-up engine vibrates more and rattles. After a few minutes things get a lot better. But then at other times issue is not present at all. I noticed at night where air is cooler and thinner engine seems better. It was running much better on a nightly drive I recently had and I was amazed at how smooth and brisk it was. 

I noticed too when starting it can sometimes be rougher and take longer to start. Driving-wise things are good although sometimes I do feel engine is excessively loud and rough (again at start-up, which then goes away after a few minutes of driving). I know cars are not as quite as when bought new as they age so just thinking wheather cleaning will restore some smoothness and quiteness to the engine as this is what I had when purchased. Tough to say. 

I do sometimes smell the rotten eggs of the cat on rare occasions. Although been told this is the clutch. I had this issue from the begining of ownership. All serviced and warrantied by offical licensed Toyota dealer. 

One issue is I believe the engine RPM's are dropping too much when engaging gear and begining to drive off at 1-2 MPH, only again interestingly on start-up. You can see that on the rev counter as the digital LED bars drop. And that makes the whole car shake and vibrate. Keeping up the revs just a little makes the entire problem go away. Still it is annoying and I was thinking whether all these issues mentioned are related to wrong air/fuel mixture. 

I have four Youtube videos on my favourites and owners have been stating once everything is cleaned all should be smoother and less noisy. 

[TonyHSD]

12 hours ago, WazWii said:

As the car has reached the mid-life-cycle stage I thought cleaning would be a good idea to preserve it for longer. 

I think there is a minor problem. Sometimes upon start-up engine vibrates more and rattles. After a few minutes things get a lot better. But then at other times issue is not present at all. I noticed at night where air is cooler and thinner engine seems better. It was running much better on a nightly drive I recently had and I was amazed at how smooth and brisk it was. 

I noticed too when starting it can sometimes be rougher and take longer to start. Driving-wise things are good although sometimes I do feel engine is excessively loud and rough (again at start-up, which then goes away after a few minutes of driving). I know cars are not as quite as when bought new as they age so just thinking wheather cleaning will restore some smoothness and quiteness to the engine as this is what I had when purchased. Tough to say. 

I do sometimes smell the rotten eggs of the cat on rare occasions. Although been told this is the clutch. I had this issue from the begining of ownership. All serviced and warrantied by offical licensed Toyota dealer. 

One issue is I believe the engine RPM's are dropping too much when engaging gear and begining to drive off at 1-2 MPH, only again interestingly on start-up. You can see that on the rev counter as the digital LED bars drop. And that makes the whole car shake and vibrate. Keeping up the revs just a little makes the entire problem go away. Still it is annoying and I was thinking whether all these issues mentioned are related to wrong air/fuel mixture. 

I have four Youtube videos on my favourites and owners have been stating once everything is cleaned all should be smoother and less noisy. 

Thanks for that. In this case then you can clean the throttle body, map sensor, run wynns car cleaner, make sure your engine oil is exact spec and changed regularly toggle with oil and air filter , check spark plugs and replace if the intervals mileage been covered and you should be good. All that strange behaviour can be from the fuel itself. Sometimes even Shell v power it’s not a good one, all depends from which place you buy it. No two garages sell the same fuel and also even one garage can sell one quality petrol one day and rubbish the next day. I use a lot of petrol weekly band noticed that long ago. I know which garages sell a good one near me with best and constant good quality and I tend to fill up there only. 

[WazWii]

5 hours ago, TonyHSD said:

Thanks for that. In this case then...

Thanks for the reply. What do you think to the RPM's dropping when setting off? When warmed up it no longer does this. There is some link with this and the clutch. Car is MMT Aygo so robotized manual. When revs drop clutch does not want to engage and shudders or maybe it is all engine related? Tough one. 

[Trewithy]

18 hours ago, WazWii said:

I do sometimes smell the rotten eggs of the cat on rare occasions. Although been told this is the clutch. I had this issue from the beginning of ownership. All serviced and warrantied by official licensed Toyota dealer. 

The rotten egg smell is caused by a reaction between the sulphur in petrol and the catalytic converter, it is a well known phenomenon.   

[TonyHSD]

1 hour ago, WazWii said:

Thanks for the reply. What do you think to the RPM's dropping when setting off? When warmed up it no longer does this. There is some link with this and the clutch. Car is MMT Aygo so robotized manual. When revs drop clutch does not want to engage and shudders or maybe it is all engine related? Tough one. 

Hi, 

I have worked on other cars like Prius and Auris hybrids and other makes and models but not  Aygo. Speaking from general knowledge and experience might not be much of a help about your Aygo mmt behaviour as some cars does have their specific needs and way of work. Something that might be strange to you it could turn to be a normal operation of this particular car.
I think best way to receive accurate suggestions and advice will be from someone who knows these cats better than me. You can try all previous suggestions we talked about and see what happens. Change the garage you fill up petrol, perhaps try Tesco momentum e5 99, or bp 97 supreme, texaco or esso and try to notice from which garage the engine runs the smoothest and stick with that place. 

[WazWii]

On 6/27/2023 at 3:37 PM, TonyHSD said:

You can try all previous suggestions we talked about and see what happens.

Thanks for all your help. I have actually started another thread regarding said issue above about vibration/shudder as it may be an issue that is related to another problem. 

[Paul john]

On 6/16/2023 at 9:25 PM, AisinW said:

E10 is about 5% ethanol amd E5 is 2.5% or less. At least in UK. The detergent PEA amount depends on which gas brand. Shell, BP, Aral, Total, Texaco, Esso, Mobil, Chevron are generally have decent detergent. 2-3x more than mininum. 

We have top tiers fuel gas stations in USA. But in Europe, this top tiers thing not that clear.  

I always thought E10 was 10% Ethanol and E5 was 5% Ethanol. 
thank you for the clarification. 

[AisinW]

😄 it is all about the wording. "Contains up to 10% ethanol" in E10 does not mean always 10%, some E5 are even 0% ethanol. We need to check it on our own using simple method (tube and dye+water). If we add water the ethanol will be adsorbed by water and separated at the bottom of the tube.