How did you work out the MPG for a quarter of a tank used? I don't your figure will be very accurate if you just did it for a quarter.

 

Sounds like you may have a fuel leak, check tank and fuel pipes/hoses for leakage

 

Well a quarter tank is around £10 the trip was 28 mile, the cost of fuel per litre is 110.9 so that calculates as 14.02 MPG.

Rick

 

12.5L is a quater
so thats even worse
lol

but i dont think the rover petrol dial is accurate, i filled mine up £30 and it dropped to half in about 10 miles. then to a quarter in about 90 but stayed in the sub quarter region for absolutely ages.

It seems to go very quickly at the top and then slow down, so red light to red light, you get MPG of about 35 if your good....

 

TBH I understand where T45 is coming from, to check economy properly, it should be on a full tank untill you fill up again and clock the mileage in between

 

I tend to fill up when it gets to just under a quarter left. Reset the trip computer after each fill up. Then at the next fill up, fill up with a whole tank of fuel then check receipt for how many litres I put in and work out the MPG using the mileage on the trip computer.

 

Where about was the needle at when before you put the petrol in?

The needles in the Zed's are terrible. My guess is that the needle was at just under the half way mark because that's just about how much fuel there was in it, and after driving it those 28 miles it went down to the quarter mark. It usually stays at the quarter mark for a while before going down again.

So what I'm trying to say is that the fuel guage seems to work in stages really, it gets to a certain bit and stays there for a bit, goes down quickly again till it gets to the next bit where it stays and so on.

I'm getting at that there was just enough fuel for the stage you were at and then after driving it went down to the next.

That was a lot more long-winded than I would have desired lol.

As said, I would check for leaks etc as well.

 

The ZR's petrol gauge is terribly inaccurate. I can be driving around with the needle at the bottom part of the 'red' notch, and I'll take the car to the petrol station and only manage to squeeze 41 litres of fuel into the tank, meaning that there's still 9 litres / 2 gallons left in the tank - or at least 70 miles of driving left!!!

My advice is - fill up the car at a petrol station you use regularly. Allow the pump to snap you off and don't attempt to put any more fuel in.
Set your trip meter to zero.
Drive until your heart is content, or at least until you've used a good portion of your petrol.
Fill up again at the same petrol station, preferably with the same pump until it snaps you off - I've found some pumps snap you off earlier / later than others. Maybe its me being pedantic.
Work out how many gallons you've put in. Look at your miles, do the math and there's a very good way of finding out your MPG.

I've just put in some new NGK Platinum plugs, definitely a good investment. Just got 37mpg from mainly urban driving, I used to get 31/32MPG. Also found that one of my old plugs wasn't sparking right (looked different to the other three plugs - abit discoloured compared to the others). Performance is loads better and 17% better MPG isn't too shabby at all. Perhaps that should be your next move for the car.

Just ignore the petrol gauge - If my 'empty' tank still has 9 unaccounted litres left inside it then it goes to show that these gauges can easily be 20% inaccurate.