[Saurabh Saini]

Originally Posted by pious_devil

Guys,
Here is my 2 cents on the topic.

In general Sulphur isn't a lubricant. However it is the process of generating ultra low sulphur diesel (hydro processing) which causes the removal of the polar components resulting in loss of lubricating properties. This results in excessive wear and damage of the fuel injection system especially the fuel pump. This is evident for any diesel having sulphur content < 500 ppm.

Hence additives are being added to maintain the lubricity and is tested via the HFRR (High Frequency Reciprocating Rig) method. Looking into the fuel composition of BS2 - BS6 , its evident that the lubricity in India is maintained @ max 460 microns. Please refer the below link for details

https://www.transportpolicy.net/stan...-and-gasoline/

Interestingly it is the European specification (EN 590) which also maintain the same lubricity.

https://en.wikipedia.org/wiki/EN_590

So what it translates to, BS4 engines will be less polluting using BS6 fuel as compared to BS4 fuel without damaging the components. Does it reduce soot, no! For that we need to increase rail pressure to around 2900 bar, increase the no. injections per cycle, use SCR and DPF. All these will be available in BS6 engines.

Hope it clarifies doubts in our minds.

I have carefully read the thread however all of the logic still doesn't clear my doubt. I am an owner of Skoda Rapid 1.5 TDI bought in 2017 and has done almost 90k kms as we speak. I also own a BS4 Duster 4x4 bought with heavy discount in Mar2020. From past 2 years I have been noticing that my skoda engine noise had increased way too much and acceleration was also affected. My last service around 75k kms the SC guys told me that its tyre noise. However, the Duster has a very bad reputation for its notorious continental Injectors which multiple users have reported. I was afraid and taking into account the bad fuel quality we accidently fill from some fuel stations on highway/hills/trips I decided to use diesel Injector cleaners. Also my duster used to make strange reving noise like in a sine wave when it was idle (sometimes) which SC guys said had something to do about injector callibration. Which they did but was only 70% effective. Hence, I ordered LIQUI MOLY and AMSOIL diesel injector cleaners recommended by a good youtuber (Chemical Engineer). Not only Duster injector noise was almost gone but also the skoda rapid engine was extremely silent as if it was new and the best part was the acceleration was restored. The youtuber alrdy mentioned that the injector cleaner contains 75% lubricants only and 25% other ingriedients like detergents to clean injectors.

Then i read this thing about sulphur content being reduced and could have long term effects on bs4 diesel engines. I quickly associated that with engine noise and started using additives every now and then. However, engine was back to noisy as soon as regualr diesel was used w/o additives. Did some more research and found that premium diesels dont have higher cetane numbers (unlike premium petrol having high octanes) but these additives which are premixed so instead of ordering on amazon/online this was a convinient method. Now i use IOCL Xtra green diesel in both BS4 cars and all issues are resolved.

My only question is if BS6 diesel is not damaging our engines, then what is????

Is it the bad fuel quality? Cz i can certainly tell that after refueling from some stations the acceleration is different(I love to rev) from others even though i just learnt that all stations irrespective of Brand (IOCL/HP/BP/Reliance) are supplied fuel from same refinery located closest to them. So the only variable i guess is the fuel station people themselves who might be adultrating the fuel.

What do you guys say?