If I use BS6 diesel in a BS4 car, will it impact its injectors? What issues will I face? How have BS2 and BS3 cars survived on BS4 fuel until now?
There won’t be a problem using BS6 fuel in a BS4 engine. Theoretically, the lower sulphur content in BS6 fuel reduces its lubricating properties, which can lead to premature wear of engine parts. However, oil companies have substituted sulphur with other additives to ensure that engine parts are well lubricated, like with BS4 fuels.