Potential Fueling Problem?

I've often put my seemingly very low MPG down to simply the way I drive on my empty roads to work, but having chatted a bit more with some other owners I'm starting to think something has gone a bit wrong somewhere.

I'm lucky if a full tank sees me 170-190 miles, having read the NA-5 tank is 50 liters that's about 13mpg.... I haven't seen any known problems or issues regarding fuel consumption before, but is there something I can check or change that might be leading to exceedingly low figures?

Does anybody have any suggestions?

Thanks for reading.

Have you filled the tank from empty ?

I was under the impression the only variation in the fuel tank size was the UK spec has 80 litres and J spec 70 litres

Have you filled the tank from empty ?

 

I was under the impression the only variation in the fuel tank size was the UK spec has 80 litres and J spec 70 litres

Exactly. I thought too UK specs were only cars that had a different fuel capacity.

Is the car your daily?

Full tank lasts me about 200 miles I haven't checked it properly but that is me honing it around and I'm a single turBo.

I can get to srd and back using about half a tank it is roughly 160miles round tip.. that's driving sensible. So on a full tank I can probably get 300miles+ driving sensibly.

I have filled it from needle under 1/5 and IRRC it cost £70+ at 58-or-something liters, still no more than 180.

It's a daily yes (although only for 3 days a week as often work from home), seems crazy that a single turbo can get 200 hooning and I use nearly a full tank doing 200 miles on the motorway (perhaps a 6th gear slightly increases MPG on motorway but surely not that much). Currently at half-empty with 90 miles on the clock, something definitely seems off.

I used to get ~350 from a tank on my NA. Try changing your O2 sensors

I used to get ~350 from a tank on my NA. Try changing your O2 sensors

Thanks mate, as I sure most know I'm not the sharpest tool mechanically, found a guide for cleaning them and will purchase new ones if nothing changes.

Edit: After reading a little more I think I'll just change them.

Thanks mate, as I sure most know I'm not the sharpest tool mechanically, found a guide for cleaning them and will purchase new ones if nothing changes.

I tried all that back in the day. Honestly cleaning mine didn't do shit, had to buy new ones.

I tried all that back in the day. Honestly cleaning mine didn't do shit, had to buy new ones.

Yeah, many people appear to be saying the same so I reckon it's just a necessary replacement job. Brace yourselves for a mega-stupid question though, I'll shortly be looking to go NA-T, should this influence my choices on O2 sensors at all?

May sound silly but check your brakes aren't binding and check the tyre pressures as well as replacing the

02 sensors

When was it last serviced ?

May sound silly but check your brakes aren't binding and check the tyre pressures as well as replacing the

02 sensors

 

When was it last serviced ?

Full service 7 months ago, really strange you've mentioned the brakes binding, you well could be onto something as I've sworn in the gap between using the engine and the clutch to inch forward at traffic lights the front seems to dip harshly when I lift off. Surely it'd be much more noticeable if they were binding though?

Think this is all pointing to a major service while I'm having everything sorted for the snail.

Full service 7 months ago, really strange you've mentioned the brakes binding, you well could be onto something as I've sworn in the gap between using the engine and the clutch to inch forward at traffic lights the front seems to dip harshly when I lift off. Surely it'd be much more noticeable if they were binding though?

 

Think this is all pointing to a major service while I'm having everything sorted for the snail.

When you park up next on the flat, just try and move the car back and forth a few inches, can you easily? The brakes normally get very hot if the seized though, from cold you could drive somewhere you know you'll have to barely use the brakes, then if you can come to a stop somewhere again with minimal braking effort you can get out and feel the heat in the four wheels and check for abnormally hot ones.

Or use a laser heat gun if you've got one or can borrow one

Or use a laser heat gun if you've got one or can borrow one

Go for a long enough drive and you can tell difference in the temperature of the alloys. It's a known issue with my MR2 so I've had it plenty of times. Some more noticeable than others. That and tyre pressures can easily trim 20% off my MPG (brim-to-brim using fuelLog app).

As a side note, I really do recommend calculating MPG properly with an app. Too many variables and inaccuracies at play when people say "I get X miles to a tank". Unless you're filling up, making a note of litres and then keeping that number in your head until you're fuel light is on and taking a trip reading.

I had a seizing caliper on the rear of my uk car and you couldn't tell with your hand that easily hence i used

my laser heat gun as i had one

Fill the tank set the trip do x miles refill tank do the math not got to remember anything, the only variable i can think of is if

the odo isn't reading correctly due to wrong wheel/tyre size, but then you could still allow for that using one of the wheel/tyre fitment web pages and quickly work out the percentage difference

4.547 litres to a gallon

Yeah, many people appear to be saying the same so I reckon it's just a necessary replacement job. Brace yourselves for a mega-stupid question though, I'll shortly be looking to go NA-T, should this influence my choices on O2 sensors at all?

Generally speaking when going NA-T the downpipes used from the turbo will not accomodate the stock O2 narrowband sensors, unless you go through all the effort of welding in a flange that you can mount the sensors to. But even that is redundant as 95% single turbo's will ditch the O2 narrowbands and stock GE ECU, as most aftermarket ECU's will interface with an aftermarket wideband O2 sensor to control AFR targets and fuel trims.