Discovery II MPG?

[Viper]

My Disco 2 does around 250 miles to 275 miles with a full tank of gas (25 gal). I checked it twice now and this is what I can do with a full tank of gas (91).
But some time a go I was abele to do 350 miles or more with one tank of gas (91).

Any advice is appreciated.

I did the last service 2000miles ago; witch was the 60,000 miles big service. (All fluids, plugs, MAF etc.)

I don’t have any OBDII codes now after replacing the MAF recently.

Help

 

[joey]

Do you have any mods on your Rover? i.e. roof rack, winch, HD bumbers, Running boards.

If it were me I would change all fluids to synthetic... both diffs, transfer case minimum.

If over size tires, this will **** fuel economy (economy funny word on a disco). Could also be the O2 sensors are starting to get dirty.

Lots of things effect fuel economy... where and how do you drive? In city all the time = lousy fuel economy. Rabbit starts = lousy fuel economy.

 

[Viper]

I don’t have any modes installed, I recently installed new tiers (265/75/16) but I had this issue before when I had my stock tire (255/65/16).

As fare as I know I asked the service ple to put all synthetic fluid, and they charged me extra for that. Just to make sure I will change the fluids again.

Don’t you think if the O2 sensors were the case I would get the service engine light on with some codes?

I drive on the freeway and city 50/50 and I always try to keep the RPM les than 3000.


I don’t see how I could do 11mpg when I should be doing minimum of 14mpg. I understand if I was doing city driving I would do around 12mpg but I do hwy too,
And I am talking about doing 70mph.

Please help…..

 

[joey]

Slow down to around 60Mph on the highway... yeah I know you will get looked at, but it will improve fuel economy a lot.

O2 sensors when they get old or dirty (remember the Disco runs real rich) it will cause it to run richer than normal... and know it will not throw a code until one of them fail....

 

[Viper]

Can I clean the O2 sensors.

 

[joey]

Sure can.... remove, take a brass wire brush and clean gentally, then finish off by using a propane torch to burn off any extra stuff.... reinstall. Front two are more important for fuel then the rear two... rear two just shows the ECU if the cats are working.

 

[Viper]

Guys I found some good information about O2 sensors link below.

http://www.mr2.com/TEXT/O2_Sensor.html

 

[Jaak]

Also look at the gas you are using. If it is blended with ethanol (~10%) your mileage will drop around 10 to 14%. Ethanol is not as potant as gasoline. Search out ethanol VS mileage ....