What is the worst mpg car you have owned (or borrowed)

Page may contain affiliate links. Please see terms for details.

RichardB

Slightly retro
Location
West Wales
Range Rover 4.6 V8 - 16 mpg average, down to 14 towing a caravan. I tested out an off-road trials course I had laid out, to see if it was doable, and it did just fine, but the onboard display registered 6 mpg. I sold it when I realised that going to see my kids was costing me £200 a time. I bought another later on, though. There has never been a car that cossets you like a nice old Rangie.

I'm currently fostering a Jag XK8 (4.0 V8) for a friend. I haven't had to fill it yet, so I can't say what the mpg is, but it ain't looking good.
 

MrGrumpy

Huge Member
Location
Fly Fifer
Current steed is a Disco 4 diesel, gets 22-23mpg towing a twin axle. I think that`s not bad ?! Low 30s cruising on the motorway. Believe it or not my first car was a 81 plate Fiesta Popular plus ( couldnt pull the skin of a rice pudding ). 950cc engine and the economy was crap, about the same as above. Horrible car it was.
 

raleighnut

Legendary Member
I've a TVR cerbera that on a track will get down to 8mpg. Normal running 15 mpg.
Aye Scott next door has a Scoobie that has been played with (balanced lightened crank, match bored pistons, bigger intercooler/turbo/injectors) and remapped to just short of 400 bhp on pump fuel and a bit over on E85 that probably does about the same.

Mind he's got a new toy now, him and one of his friends have bought an old Landrover Discovery for proper off-roading, he had it out last weekend and it came back with the standard front bumper ripped off (he's ordered a new aftermarket one with winch attachment) and with a good hundredweight of mud plastered to it and one tyre ripped to shreds (luckily it had a spare)
They started with a full tank, drove there, then did about 30 miles in the venue and drove home (12-15 miles) and it's on empty but 2 blokes had unbelievable fun for a day and can't wait to do it again :becool:
 

SGG on a bike

Senior Member
Location
Lowestoft
I've a TVR cerbera that on a track will get down to 8mpg. Normal running 15 mpg.
I can relate to that. I’ve got a Maserati 3200gt. Last time on the dyno it showed 406bhp at the wheels. Normal driving around is in the mid-late teens. Took it to Bruntingthorpe a few years ago and managed 58 miles on half a tank (15 of which was getting to the track from the hotel).

Mate of mine has a 1929 Model A with a tuned Cleveland V8. Never gets out of single figures. The previous owner had it running a supercharger and two 4 barrel Holley carbs. It’s much better now it’s on a single 4 barrel without the blower.
550418
550419
 

Cavalol

Guru
Location
Chester
Borrowed a Shogun V6 petrol (3.0, iirc) a few years back that was absolutely frightening on fuel. Had it two days and gave it back, decided to cycle to work instead.

Just bought this, though, which might compete with that...

1602261113490.png



... pictured in what will probably be its natural environment this morning. It's a 5 litre petrol and an absolute beast of a car.
 

Cletus Van Damme

Previously known as Cheesney Hawks
1998 Subaru Impreza UK Turbo wagon. I never got over 17 mpg from it no matter how I drove it. It had horrendous piston slap when it was cold. My brother at the time had a 1998 UK Honda Integra Type R DC2, I had a race with him on a quiet straight and was disgusted that they were identical in acceleration. Considering that car would do about 35mpg if kept out of VTEC, it had less torque by a long way, but a better built car and the best handling front wheel drive car I've ever driven by some way.

I think if I was ever to buy another Impreza, which I'm sure I wouldn't, it would have to be an STI, something with more power to justify the horrendous fuel economy. Then again I'd rather have another MX5 to be honest.
 

Drago

Legendary Member
Ill be looking after Daughter #1's Cayenne Turbo S for a few days. 4.5 litre twin Tubby V8, 550ish bhp, 34 tonnes, aerodynamics of a tower block....if I could afford the fuel id take it out and see how low it'd go.
 

rogerzilla

Legendary Member
A 2012 Vauxhall Astra that Europcar lent me when I drove my MX-5 into the back of a lorry (at < 5mph, but that was enough to roll up the bonnet due to the height difference).

I said I didn't want an automatic. They said have this auto, or you'll be here for hours.

I have never driven anything that produced such little power from so much fuel. 29mpg over two weeks and it was dog-slow. I write as someone who drove Micras for years.
 

gbb

Legendary Member
Location
Peterborough
I recall reading an article saying the smallest 2.0 engine in a Granada, because it had to pull a heavy car around, had similar efficiency to the 2.9V6.
We had a Rover 800 2 ltr, same scenario, big car, engine too small, heavy fuel consumption.
I also remember the Audi A4 1.8 when it first came out...I cant remember if it was turbo'd but I remember finding it was stodgy to drive, remarkably plain inside..and used a lot if fuel. Never saw the attraction in the early ones (I don't in the later ones for that matter)
 

rogerzilla

Legendary Member
The main weakness of the NEDC fuel economy and CO2 test was that (because even the slowest vehicle had to be able to match the speed profile) engines were never worked hard. This meant that small turbo engines, especially petrol ones, show an enormous disparity between test figures and real-world driving, because a turbo engine absolutely guzzles fuel when the turbo is on boost*. Look up one of the "real mpg" guides for cars like the Fiat 500 TwinAir. Cars without turbos, now a rarity, got much closer to the test figures in real life.

A couple of examples (first is a tiny turbo engine, second is a larger NA engine):

https://www.honestjohn.co.uk/realmpg/fiat/500-2007/09-twinair-85-dualogic

https://www.honestjohn.co.uk/realmpg/mazda/mx5-2005/20i

The new WLTP cycle produces more realistic numbers

*mainly because the mixture has to be enriched to prevent detonation unless it is an old-school turbo engine with a very low compression ratio of about 8:1, which is inefficient ALL the time.
 
Last edited:
Top Bottom