Hopefully i can help..
It certainly would depend on the cars intial use wise to see any sort of benefit as mpg/performance/reducing dpf issues..it can in sense increase mpg slightly/aswell as able to run the run the engine alot quieter aswell as reduce smoke and get a better responce from the engine - but as you'll know will be a little more expensive than your regular diesel - in my opinion there isnt really much differance really other than using a good regular diesel - try and avoid supermarket fuels and adding a fuel additive every so often like millers/forte diesel additive..probably the best times you would use premium diesel along with regular would be around the winte/colder months..but theres nothing wrong in filling up say once a month on premium if prefered..I do hope this helps
would premium diesel fuel help with EGR valve failures - I have had two replacements in 3 years? Or are there other measures that can help to prevent EGR failures?
Hi..sorry for the delay..
Depends on the type of failure..if its just coated in soot/carbon..normally they can be cleaned up and then refitted back without to much expense,,if it an actual control problem with the valve not opening or closing then it can only be replaced - usually the reason for clogged egr valves is lack of use the car i mean and or prolonged idling of the engine - as above a higher octane/premium would help ina sense but most people tend to add regular aswell as the occassional diesel additive..I do hope this helps further