AN additive or particular fuel to increase mpg?

[smile of life]

I have an ML320. You happily watch the fuel guage go down whilst driving sensibly.

Can anyone suggest a particular petrol (eg Optimax), or additive, or engine tweak that can decrease petrol consumption without adjusting my driving style? I don't want to increase tyre pressure because that changes the handling dynamics and can render the tyres more dangerous.

And it can't just be an expensive fuel option as that defeats the object of the exercise.

Any thoughts that can benefit us all?

Thanks

 

[jberks]

Thats why most people buy the diesel I'm afraid.
Baiscally, no, you may tweak an extra 1-2mpg here or there but nothing that you'll actually notice at the pumps. Some people say that the higher octane fuels like optimax etc make a difference. From the discussions on here before, my impression is that they only have an effect on the older cars (W124 etc), possibly something to do with knock sensors but the only difference I found on my 2000 E240 v6 was an extra £5 on the fuel bill.
All 4x4's are thirsty. I have a jeep diesel and that's only just bearable.
You could consider an LPG conversion but at £2k plus finding a convenient supplier you have to do a fair few miles just to get your money back and it would actually be cheaper for most people to pay the extra to swap to a diesel, especially when depreciation is taken into account.

 

[philharve]

Hi smile of life

I recently conducted an experiment by switching to Optimax from an ordinary, non-detergent supermarket fuel and have decided to stick with Optimax even though it costs me GBP5 - 6.00 pounds more per refill. The better acceleration and smoother running is appreciated but I would not have stuck with Optimax if it didn't give more mpg. I am presently noting an improvement of around 8 - 10% per tank (45-mile) which is worthwhile and cost effective for me because Optimax is less than 92p/litre where I live. If Optimax had been nearer a pound per litre I would have reverted to a cheaper fuel. I could save myself a couple of pennies per litre by using Shell unleaded but I've found Optimax to be that little bit more superior. I think having a detergent-based fuel is an advantage because it is kinder on the engine and could reduce running costs in the longer term.

If you study the contributions in another threads that discuss Optimax you will discover that not every MB owner reports an improvement. The age of the vehicle is a factor and whether, or not, it has a knock sensor.

I will stick with Optimax for now but will give other high performance fuels a try once I locate them. Branded fuel outlets are not all that common in SW Cornwall. I have to travel around 12 miles to fill up with Optimax.

REGARDS Phil