Thanks for recommending Shell V Power fuel - I use it in my 1996 Cadillac Deville.

Having read a number of car articles in the Daily Telegraph (yes, some of us in the "Colonies" do read material from outside our borders), I noted your advice in using high-quality fuels, not just for mileage improvements, but to keep some repairs less likely. I own a 1996 Cadillac Deville, which, although not having a reputation for fuel economy, actually does rather well in that department. Depending on conditions, I get anywhere from 24 to 28mpg (US gallons), with occasional spurts to 30mpg. This from a sizeable fuel-injected Northstar V8 with close to 300 horsepower and 130,000 miles on the odometer. I previously used the cheapest gas I could find, but decided to switch to Shell V-Power to see if there really was any improvement. What a difference. The car runs much smoother 500 miles into the change, my gas mileage has increased by ten percent, and it is still creeping upward according to the on-board computer. The car responds faster when passing, and the "stumbling" I've experienced at low RPM has been reduced considerably. Thanks for the good advice, and keep up the good work.
Great news. Thanks for the support. In the summer (generally 15C +) I get around 54 miles per UK gallon from a Fiat 500 1.2 petrol for the same reasons you describe. It runs much cleaner at low revs. Ford has always reckoned that on a 200 horsepower engine, a 99 Ron fuel like V-Power is good for an extra 25 horsepower. Of course, manufacturers dyno test and rate their engines on the best fuel, so running on 95Ron you actually get less than the stated power output.
Answered by Honest John on

Ask Honest John