Using 92 Octane Instead Of 95 Octane

[thusira]

Hi,

My car (toyota vitz 1000cc) is been using 95 octane for the last two years. I am thinking of moving it back to 92 Octane. What procedure should i follow. is it a just refilling or do i have to do the engine cleanup ? Please help me with this .

Thanks in advance.

[VVTi]

Why do you want to do that? If the car is rated for 95 why you switching to 92?

[The Don]

  On 11/11/2014 at 6:35 AM, VVTi said:

Why do you want to do that? If the car is rated for 95 why you switching to 92?

Don't think the car is rated for 95, but a lot of people switched to it after the last petrol debacle

[Davy]

  On 11/11/2014 at 5:56 AM, thusira said:

Hi,

My car (toyota vitz 1000cc) is been using 95 octane for the last two years. I am thinking of moving it back to 92 Octane. What procedure should i follow. is it a just refilling or do i have to do the engine cleanup ? Please help me with this .

Thanks in advance.

Simply start filling in with 92 octane if the manufacturer has specified that 92 octane is okay. You need not follow any specific procedure.

[Sierra Charlie]

Pardon my question here. But is there a difference of fuel consumption for 92 and 95 octane petrol on a given engine? One of my friends claims that he's been getting low km/l on 95octane when compared to 92octane.

[Dinukap4]

  On 11/11/2014 at 1:18 PM, Sierra Charlie said:

Pardon my question here. But is there a difference of fuel consumption for 92 and 95 octane petrol on a given engine? One of my friends claims that he's been getting low km/l on 95octane when compared to 92octane.

Very true this happened to my Rav4 this was back before the 92 octane gimik, I pumped 10L of 90 petrol and it did about 10kmp/l with 95 it only did like 6-7 Kmpl

[Rohnd]

Most of the new gasoline engines well run on 92 , in engines specified for 95.

Those are equipped with special technologies to diminish the pinging which can be harmful

with low octane fuels.

The carbon sediment can be high, when use 95 octane on 90 or lower specified engines.(other way)

[kmeeg]

  On 11/11/2014 at 5:56 AM, thusira said:

Hi,

My car (toyota vitz 1000cc) is been using 95 octane for the last two years. I am thinking of moving it back to 92 Octane. What procedure should i follow. is it a just refilling or do i have to do the engine cleanup ? Please help me with this .

Thanks in advance.

A minor point apart from the technical aspect of minimum octane level for the engine. I can remember sometime back we had a huge problem with poor quality petrol. I was pumping Oct95 and did not had any issue but some of my friends who pumped regular petrol was affected with the poor quality petrol. You guys still remember that??

BTW, minimum octane level is mentioned in the owners manual. And some cars it will show minimum octane level in your fuel cap. Also to note that this is not limited for cars, it applies to any engine that run on fuel (generators, compressor, etc...). Correct me if i'm wrong..

[The Don]

  On 11/11/2014 at 3:05 PM, Rohnd said:

Most of the new gasoline engines well run on 92 , in engines specified for 95.

Those are equipped with special technologies to diminish the pinging which can be harmful

with low octane fuels.

The carbon sediment can be high, when use 95 octane on 90 or lower specified engines.(other way)

I don't think this is the case. If a manufacturer has made an engine to run 95ron and you run 92, you will always have at least a bit of pinging. Its very difficult to eliminate it and quite frankly if they could they won't specify a minimum ron number.

In SL we get vehicles designed for 100 ron as well, which are run on 95 but though they start and run, the power is not the same and there is always a bit of pinging.

[Dinukap4]

  On 11/11/2014 at 5:46 PM, The Don said:

I don't think this is the case. If a manufacturer has made an engine to run 95ron and you run 92, you will always have at least a bit of pinging. Its very difficult to eliminate it and quite frankly if they could they won't specify a minimum ron number.

In SL we get vehicles designed for 100 ron as well, which are run on 95 but though they start and run, the power is not the same and there is always a bit of pinging.

Like the GDI montero's we used to have I think they were recommended to use 100 i can remember because I hesitated to buy because of this reason.

[edsal]

Hello Guys,

My experience on this subject. I own a Honda Vezel 2014 model 1.5L engine, and I wanted to know the best petrol to use in Sri Lanka and I was unable find this information because all the info was in Japanese (after Translation) said use “Regular” with the fuel octane rating not listed any where.

· My first discussion with Honda local agent and the service adviser said “you must use high octane 95 otherwise bad the engine will damage because this is a direct injection engine”

· I did some reading and found Regular unleaded petrol in Japan as following:

Regular petrol – 87 octane

Regular Plus - 88 and 89 and 90 octane

Premium - 91 octanes

· Based on this information I started filling up with Lanka IOC Euro 3 with 91 octane rating (5 rupees lower than the super 95 octane) and happy say the following benefits in driving my Honda Vezel 2014.

1. Better fuel economy KM/L has improved by 30%.

2. Overall improvement in engine performance runs much smoother, quiet, better response and improved acieration and never heard any pinging or laboring of the engine.

[ramishkad]

  On 11/12/2014 at 4:33 AM, edsal said:

1. Better fuel economy KM/L has improved by 30%.

2. Overall improvement in engine performance runs much smoother, quiet, better response and improved acieration and never heard any pinging or laboring of the engine.

Were these improvements when you switched from 92 Octane to Euro 3 or 95 Octane to Euro 3?

[edsal]

Hi, This benefits when I switched from super 95 octane to Euro 3. i never used 92 octane. regards

[bycap]

  On 11/11/2014 at 1:59 PM, Dinukap4 said:

Very true this happened to my Rav4 this was back before the 92 octane gimik, I pumped 10L of 90 petrol and it did about 10kmp/l with 95 it only did like 6-7 Kmpl

Seriously ??? I thought this other way round. Just wondering why this happened ?

[Rumesh88]

  On 11/12/2014 at 4:33 AM, edsal said:

Hello Guys,

My experience on this subject. I own a Honda Vezel 2014 model 1.5L engine, and I wanted to know the best petrol to use in Sri Lanka and I was unable find this information because all the info was in Japanese (after Translation) said use “Regular” with the fuel octane rating not listed any where.

· My first discussion with Honda local agent and the service adviser said “you must use high octane 95 otherwise bad the engine will damage because this is a direct injection engine”

· I did some reading and found Regular unleaded petrol in Japan as following:

Regular petrol – 87 octane

Regular Plus - 88 and 89 and 90 octane

Premium - 91 octanes

· Based on this information I started filling up with Lanka IOC Euro 3 with 91 octane rating (5 rupees lower than the super 95 octane) and happy say the following benefits in driving my Honda Vezel 2014.

1. Better fuel economy KM/L has improved by 30%.

2. Overall improvement in engine performance runs much smoother, quiet, better response and improved acieration and never heard any pinging or laboring of the engine.

Are you sure you had a 30% improvement in fuel economy due to change in fuel type alone and that too from 95 to 91? While hybrids are less sensitive to fuel type than conventional engines (for they are designed with fuel efficiency in mind but not the power performance) I simply cannot believe a 30% improvement on a single factor!

[VVTi]

Talk about pulling numbers and facts out of one's arse...

[YALA]

  On 11/12/2014 at 9:55 AM, VVTi said:

Talk about pulling numbers and facts out of one's arse...

yeh second that there is no way you can get a 30% boost in economy. actually this is the first time im hearing of a 30% boost by simply upgrading 3 octanes.

[VVTi]

  On 11/12/2014 at 11:18 AM, YALA said:

yeh second that there is no way you can get a 30% boost in economy. actually this is the first time im hearing of a 30% boost by simply upgrading 3 octanes.

If the numbers are right, there is a good market for Octane boosters....

People talk out of their arseholes sometimes, they should stop to think a bit. Your average hybrid car owner is similar to the Satakaya balakaaya member... with all the fairy tales to the uneducated retards of the country about how much of an ArseCharya this country and how great is the low price of bombai loonu under this government is.

LOL.

[asrock]

  On 11/12/2014 at 11:18 AM, YALA said:

yeh second that there is no way you can get a 30% boost in economy. actually this is the first time im hearing of a 30% boost by simply upgrading 3 octanes.

Thats downgrading by 3 octanes right?

[ramishkad]

  On 11/12/2014 at 5:49 AM, edsal said:

Hi, This benefits when I switched from super 95 octane to Euro 3. i never used 92 octane. regards

Thanks for the info. But how did you isolate that the fuel efficiency boost was due to the fuel type change? It probably was difference in driving conditions, traffic status, type of driving etc during the period that contributed to this?

[Rohnd]

  On 11/11/2014 at 5:46 PM, The Don said:

I don't think this is the case. If a manufacturer has made an engine to run 95ron and you run 92, you will always have at least a bit of pinging. Its very difficult to eliminate it and quite frankly if they could they won't specify a minimum ron number.

In SL we get vehicles designed for 100 ron as well, which are run on 95 but though they start and run, the power is not the same and there is always a bit of pinging.

92 & 95 bring little difference for modern electronically controlled vehicles. Very short/little pinging will not harm engines.The Anti Knock Sensor does this duty to suppress the pinging. In some vehicles not fitted with this device or with faulty device, may produce some octane dependent pinging.

Vehicle's health also has a major contribution to this. We cannot compare 10 years old vehicle with nearly new vehicle in terms of fuels octane responses.

It is correct low octane fuels can attribute very little fuel saving, but not in 30% range. This cannot be explained in theoretically , but could be other factors such as ambient temperature , Driving patterns , spark plugs conditions/ratings etc

Edited November 13, 2014 by Rohnd

[The Don]

  On 11/13/2014 at 12:32 PM, Rohnd said:

92 & 95 bring little difference for modern electronically controlled vehicles. Very short/little pinging will not harm engines.The Anti Knock Sensor does this duty to suppress the pinging. In some vehicles not fitted with this device or with faulty device, may produce some octane dependent pinging.

Vehicle's health also has a major contribution to this. We cannot compare 10 years old vehicle with nearly new vehicle in terms of fuels octane responses.

It is correct low octane fuels can attribute very little fuel saving, but not in 30% range. This cannot be explained in theoretically , but could be other factors such as ambient temperature , Driving patterns , spark plugs conditions/ratings etc

Anti knock sensors have been fitted to vehicles from the 1990s. I don't think you understand why you have to use the correct octane rating for the vehicle you are using. It is not just to stop pinging. Pinging is a symptom not the disease. The disease is that the ratio of compression envisioned by the manufacturer demands a different ron rating from the fuel than the one supplied. And while you could make the engine run smoother by adjusting parameters like the rpm, which the ECU does, you cannot eliminate the problem, and the engine will never produce as much power as it was designed for, leading to higher fuel efficiency, engine wear due to having to race a lot to get acceloration etc etc.

A internal combustion engine is still a very mechanical device. While as there are certain things the ECU can adjust to rectify certain issues it cannot adjust the stroke, it cannot adjust the shape of the piston, the chamber, the angle of the valves etc etc. Everything is in a fine balance in a modern precision engineered engine.

[YALA]

  On 11/12/2014 at 11:23 AM, asrock said:

Thats downgrading by 3 octanes right?

My bad. and in essence i dont think any other factors change drastically enough to effect fuel in the short/medium run. unless you do a round trip to jafna and back which still wont give a 30%. Only other factor i can think of is a clean up of the MAF and replacement of oxygen sensors upstream and downstream

[Rohnd]

We cannot separate octane subject with engine detonation. In history high octane used in Aviation fuel came as

remedy to detonation in small gasoline engines well before the engine management concepts.

Yes, Pinging is a symptom , detonation is the action. We can see many vehicles in 2000 onward not fitted with

anti lock sensors or similar even in leading makes. These cars prone to more detonation if use low octane fuels.

Many years back AutoLanka forum discussed effect of Mobxx 1 with octane 95 fuel which was not favorable to engines, specially Toyotas with VVT. It was mentioned that these cars ran well on 91 fuel.

I do not understand Japan fuel ratings quoted by edsal (in this tread) while JDM specify fuel rated to up to 95 or more.

I hope this octane matter is now outdated since this had been identified since 1940s or before. Americans put high octane index fuels first probably due to their large capacity engines ( >3L) which were more prone to damage due to high level of detonation.

As Don said you must refer owner's manual and use specified rating of Octane.However 100 rated fuels still mot avaliable here, the CPC should be blamed.

[vishkid]

IIRC 100 is not the ultimate octane (RON) though, it's just better than 98? But I don't think there are many road cars requiring anything above 100. Even 95-100 is required by a handful of models and probably doesn't justify maintaining a separate stock?