Looking at the
Shell site and a few other pages it looks like the difference between normal and V-Power diesels is down to the cleanliness of the burn and the additives that are supposed to keep the injectors clean. I know from my dadâs experience that his 1.9 TDI sees a gradual drop in fuel economy until he uses something like Redex to give it a cleanout and itâs like new again (in terms of economy). No doubt there will be other parts of the system that will be clogged up still and I reckon using a cleaner fuel would be a good idea if you have a DPF, in the long run anyway.
Point to note, the difference between normal and V-Power
petrol is totally different. The higher octane rating means the engine can run at a higher compression ratio which gives the performance and economy gains.
Modern engines have the ability to adjust the compression ratio so theyâre able to cope with various available fuel types. For example in the UK we have 95 RON for unleaded and Super is normally 97-99 RON. In Germany their unleaded is 91 RON, Super is 95 and Super Plus can be up to 100 (I used to use Shell Optimax 100 when I was over there).
Older non-performance engines will probably run at 95 RON, if theyâre unable to adjust their compression ratio putting anything higher than that in is a waste of money.