Decreased fuel economy in wizard?Why??

[jane]

HI can anyone point me in the right direction of what I can do do improve fuel economy. I was always so proud that my 97 wizard did over 650 km per tank but of late I am only getting 500km which is significant with the price at present. What shoould I be looking out for and how can I improve this. Would appreciate some help, Thanks

[Bruce]

Hi Jane, first thing where are u NZ or Aus etc? Now have u stopped using additive? changed tyre size or done any mods?
I've had a similar situtation with our MU (also have a Wizard) but I had stopped using the additive, put it back in and it is improving (dont run the Wizard on it why as it was not on it when I brought it)
When working out your economy you should always use your trip meter with fuel used. My MU dropped to 6.7 kpl and that is terrible ,but I had only put 15 litres in and may not have fulled it properly. As you can see there is many variables.
Cheers Bruce.

[jane]

HI, thanks for your reply, nothing has changed, I am in NZ , dont use additives, didnt know there was any for diesel, certainly havent done any mods either that is why I am at a loss to understand why it has dropped when I am doing exactly the same travel each week,

[geeves]

The obvious ones Bad air cleaner, bad fuel filter. The less obvious ones Torque converter lock up not working,low tyre pressures, binding brakes, changeing traffic conditions ie what sort of running do you do,cold weather diesel, leaking fuel pump Put your hand down the back of the pump if it comes out wet this will be obvious, injector probs Does it smoke more than before.
These are in order of thinking about them check them in order of easyness. Also your fuel gauge might be faulty How many liters are you putting in?

[jane]

Thanks for all your feedback, Can you tell me wher to locate the fuel filter as I dont have a manual, thanks

[geeves]

There is a square bracket holding a round assembly about half way down the left hand inner gaurd. This has a small round knob on top. This knob is the priming pump The filter hangs underneath it and looks like an oil filter. There is a procedure for changing it.
I trust we are talking a 3.1 diesel engine. On the firewall id plate it will have an engine number. If this starts "4jg2" all the above is correct. If it starts "4jx1" or "6vd1" we have to start all over.
the 4jg2 is the diesel engine used in bighorns from 92 to 97 Mus from 94 to 97 and wizards in 96 and 97
The 4jx1 is the new type fully electronic diesel that is a truely magic engine when going right but the devil incarnate when it isnt.It was released in 97
the 6vd1 is the v6 petrol that has been around long enough to be tried and true. We dont hear of many problems apart from the cost of fuel

[roscoe46956]

Hi Jane, I have a 97 Wizard with the 4JX1 Engine so I may be able to help if you have the same vehicle.

Cheers
Roscoe

[Burty]

My 3.1 MU was consistently getting 720 - 730 km per tank (tripmeter reset at each filling) and filling up when the fuel gauge needle rested squarely on empty. Then things dropped down to 670km per tank. I then did an oil change (delo 400) and put some wyns spitfire in the tank and it went up to 750km and has now settled back to round the 720km mark.