Poor Fuel Consumption

[mattashton]

HELP!
I have a 1996 MX-3 V6 and its completely standard, But the fuel consumption is really bad!
I am currently getting just over 200 miles to a tank of petrol, even though i have been driving it really carefully.
I have only had the car for 3 weeks, and the first week i just thought that it was me being a bit heavy on the gas.... so the next week i drive really carefully, with not much improvement!
I love the car but the fuel bills are stupid!
I hope someone can help me... thanks in advance

[lakersfan1]

Even a properly tuned one usually only gets 250 miles a tank with nice driving. The fuel tank is unusually small, though. Although 23 MPG still isn't great IMO.

Look at a new cap and rotor, and possibly new O2 sensors and see if that helps your MPG a tad.

[IanL]

The worst my (unmodified) car has done is 25 mpg (imperial gallons), and the average is 30. I inadvertently ran my tank dry, and when I refilled, it took only 45 litres, even though the nominal capacity is 50. So when you say "a tankful" I assume that's less than 45 litres, say 9.5 gallons (imperial). That's 21 mpg. But if you're going by the gauge - don't. It shows empty after about 35 litres (7.7 gal) have been used. That would mean you're getting 26 mpg. You really need to know how much you put in to fill the tank.

Lots of engine things to check (plug gaps, clean air filter, O2 sensors), but first check the brakes. Its not unknown for the handbrake not to release fully, and/or the calipers to bind. Go for a drive using the brakes very sparingly, then feel the disks. If they're really hot, check the calipers and the handbrake action.

<small>[ February 25, 2004, 09:37 AM: Message edited by: IanL ]</small>

[mattashton]

Thanks, i will check the things you mentioned.
I worked the mpg out to be about 23mpg (£32.00)
I love the car, so im just hoping that i sort the fuel prob out or it will have to go!
I have read elsewhere on the forum about resetting the ECU, by disconnecting the power for 30secs. do you think that this will help (im gonna try it anyway)
Cheers

[lakersfan1]

Originally posted by Lord_Matt:
Thanks, i will check the things you mentioned.
I worked the mpg out to be about 23mpg (£32.00)
I love the car, so im just hoping that i sort the fuel prob out or it will have to go!
I have read elsewhere on the forum about resetting the ECU, by disconnecting the power for 30secs. do you think that this will help (im gonna try it anyway)
Cheers

I honestly don't think you'll get much more than 23MPG, even if you give it a good tune up and replace the parts mentioned. But can't hurt to try. You'd want to reset the ECU after the tune-up parts re replaced. You're computer would eventually adjust without resetting it, but it will learn much faster if you reset it first.

[UoMDeacon]

23mpg really isn't that bad, considering our cars are EPA rated for 20-23mpg city and ~27mpg for highway driving. I usually average around 25-26mpg on a fill up with my car.

[IanL]

We Brits have bigger gallons, so 23 US mpg = 27.5 UK mpg, and 23 UK mpg = 19 US mpg

[UoMDeacon]

Ahhhh...ya crazy brits

[mattashton]

Maybe i should get a towbar and tow a petrol tanker behind the car?

[SimonPK]

I get a regular 32mpg (UK) from my KLZE on a 40 mile city commute every day - 56 sets of traffic signals and no speed faster than 80 km/hr. My old K8 got around 33mpg - I can't imagine how fast you guys would have to drive to get 23 mpg!!!!!!

[mattashton]

That was the whole point of me starting the thread.... I havent been driving fast!
If i had been driving hard and fast i would not be bothered about getting only 23mpg.
I have been driving really carefully so i would expect much better fuel consumption than the 23mpg that i am currently getting.
I am going to check the things suggested to me earlier in this thread this weekend and hopefully resolve the problem.
but if anyone else has any good suggestions i would be very greatful for thier help.
Thanks

[quicksliver]

I drive my car hard and fairly fast. Usually 20-30km/h over speed limit...i know, don't have to lecture me on it. Anyhow, i get between 400-450km's for every 40L of gas.

[mattashton]

Just filled up my car...
41.87 Litres or 9.210 Gallons(UK)
215.6 Miles.
23.41 MPG (UK)
That cant be normal Mx3 performance considering i havent been above 3000rpm all week!
Please send petrol donations to:- matt@..
LOL

[IanL]

Tanker on the way

[valoncan]

I Live in Ontario Canada, I put 420-450 km with 45 litres. Literally my tank was chocking from gas when I filled it, and then I drove it to work and home, literally commuting. It was empty at 430 or something, when i went to fill it up it did not take more than 44 litres and some change.
I drive really relaxing, and no more than 2500 rpm, in other other words low shift.
There were times that it went to 448 or something km with exactly 45 litres.
I have all new parts though, like the disty, cables, sparks, O2 sens, pcv valve, clean throttle, new K&N filter, and more.
But even when I bought it, it was doing real good.
I found that BOCH +4 plugs help a lot. I mean these are no gap plugs and they,re much more expensive that the regular, but it does help on fuel efficiency.

Good luck