Poor MPG

[Rannsachair]

V6's are always thirsty, 31 mpg is not bad, my Chevy did around 10 in town and 25 on a run, that was a 4.3 litre auto. Pug is around 35 and the Alfa did about 36.

My Wife's Lexus RX450h, 3.5 V6 300hp hybrid, 2.2 tonne SUV averages 35 mpg, I can get 85mpg out of my 1955 Matchless motorbike.

 

[AVI_8]

Diesel is for tractors and lorries... for sure mate!

The first time I can honestly say a don’t agree with you there, my X3 has a 3.0D, twin turbo, considerably more torque than a V8 petrol at 650nm and 380 hp, ok it’s been remapped, under 5 seconds from 0-60 though that’s not the way I drive it, but more importantly just normal driving I get 34 mpg on average and 38 is usual on a long drive, and I don’t drive slowly, if my wife was driving 40 + mpg would be achievable

 

[AVI_8]

As mentioned in another thread, I’ve swapped the Disco 4 for a 2018 Volvo V40 T3 petrol, 34,000 miles.

It’s getting the same usage, and is also an automatic, but is only doing 31.6 mpg. We got nearly that in the 3 tonne, 3L Disco. This car is half the weight and has half the engine, and is eight years newer. It’s almost bad enough to consider rejecting the car, since making the swap was mainly to reduce running costs.

I’ve checked brake discs with the infrared thermometer after a run, and they’re all under 30*C. Will check tyre pressures. Other than looking at fuel trims/MAF/MAP etc, is this to be expected from a modern car?

I’d say an average of 31.6 is about right for a petrol car, to test it, zero the count on a long run and see what you get as it can make a big difference, it’s the urban driving with stop starts which ruins your mpg.

 

[Bornfree]

As mentioned in another thread, I’ve swapped the Disco 4 for a 2018 Volvo V40 T3 petrol, 34,000 miles.

It’s getting the same usage, and is also an automatic, but is only doing 31.6 mpg. We got nearly that in the 3 tonne, 3L Disco. This car is half the weight and has half the engine, and is eight years newer. It’s almost bad enough to consider rejecting the car, since making the swap was mainly to reduce running costs.

I’ve checked brake discs with the infrared thermometer after a run, and they’re all under 30*C. Will check tyre pressures. Other than looking at fuel trims/MAF/MAP etc, is this to be expected from a modern car?

My mate had a Volvo V40 company car it was a 1.4 turbo petrol hybrid. It would only do 32mpg on a long run. Fortunately it had a major transmission failure on the M11 and left a trail of cog's,oil and alloy casting all over the fast lane. The main dealer fitted a new transmission under warranty he got the car back and it had no power, back to the dealer and the diagnosed a twisted crankshaft so the car was scrapped.

 

[JOEPRO]

All these figures sound like Priuses!

(Merc S600 V12 Bi Turbo)



This car can go down to an indicated 4.5mpg on certain cold town trips / traffic to Tesco etc. Never goes above about 15mpg on long trips. There is no replacement for displacement though.

A long trip over hills 9.2mpg over 69 miles

 

[Robotstar5]

I’d say an average of 31.6 is about right for a petrol car, to test it, zero the count on a long run and see what you get as it can make a big difference, it’s the urban driving with stop starts which ruins your mpg.

I can only dream of that, I get around 21 mpg urban and 28 mpg on a run (2.4L 4 cyl auto SUV) and I am pretty gentle with the throttle, I bet it would be sub 20 mpg if Mrs "Leadfoot" Robo drove it

 

[bricol]

Lancia currently on the daily commute, and trailer hauling duties of lots of heavy stuff away from my mums . . . no idea what it's getting but if it breaks 20mpg I'd be amazed.

Having said that - when it used to be my one and only daily driver, the weekly commute, starting with a full tank of petrol on Monday morning, the light would be flashing on and off Thursday evening, on almost all the time Friday morning, and I'd chicken out on the way home Friday afternoon.

Post covid, a bit quieter roads, a realisation I don't actually need to rush to work, and probably just getting old . . . its now the Thursday of the following week the light comes on!

 

[Robotstar5]

Lancia currently on the daily commute, and trailer hauling duties of lots of heavy stuff away from my mums . . . no idea what it's getting but if it breaks 20mpg I'd be amazed.

Having said that - when it used to be my one and only daily driver, the weekly commute, starting with a full tank of petrol on Monday morning, the light would be flashing on and off Thursday evening, on almost all the time Friday morning, and I'd chicken out on the way home Friday afternoon.

Post covid, a bit quieter roads, a realisation I don't actually need to rush to work, and probably just getting old . . . its now the Thursday of the following week the light comes on!

Since I retired it can sometimes be a couple of months between fill-ups for mine.

 

[Wedg1e]

I dreeeeeeam of 31mpg. <<< that thing over there averages 18mpg.
Yes, it will do about 25 if I bimble down the motorway at 55mph, but who the hell wants to do that?

I get mid-40s from the ST1300 and about the same from the works' Connect. Both can do 50+, but you have to bimble like Reginald Mulhusband and Augustus Windsock.

 

[premmington]

The first time I can honestly say a don’t agree with you there, my X3 has a 3.0D, twin turbo, considerably more torque than a V8 petrol at 650nm and 380 hp, ok it’s been remapped, under 5 seconds from 0-60 though that’s not the way I drive it, but more importantly just normal driving I get 34 mpg on average and 38 is usual on a long drive, and I don’t drive slowly, if my wife was driving 40 + mpg would be achievable

I have had diesels for years - I still got one - but when that reaches end of service - there will be no more diesels for me!

It will be small petrol cars from now on - I am older and don't need big vehicles - plus there is the environmental issue of particulates running a diesel.

 

[AVI_8]

I have had diesels for years - I still got one - but when that reaches end of service - there will be no more diesels for me!

It will be small petrol cars from now on - I am older and don't need big vehicles - plus there is the environmental issue of particulates running a diesel.

Fair point, it’s micro plastics (which are now in clouds) if the newspapers are to be believed that personally bothers me more than anything that escapes a diesel particulate filter. As long as it accelerates with a reasonable shove and doesn’t need plugged in to refuel it I’ll drive it.

 

[8ob]

Petrol engines can only get close to a diesels economy on a very carefully driven run, in town they don’t even come close. Typically diesels on low rpm use ( idle and stop start traffic) can run as high as 70.1 + fuel air ratios, even the big v8 yank diesels only use 1/3 of a us gallon an hour at idle.

Bob

 

[Puglet1]

The first time I can honestly say a don’t agree with you there, my X3 has a 3.0D, twin turbo, considerably more torque than a V8 petrol at 650nm and 380 hp, ok it’s been remapped, under 5 seconds from 0-60 though that’s not the way I drive it, but more importantly just normal driving I get 34 mpg on average and 38 is usual on a long drive, and I don’t drive slowly, if my wife was driving 40 + mpg would be achievable

Hmm. Is this the N57 straight 6 engine as fitted to the police cars?

 

[Ubique]

All these figures sound like Priuses!

(Merc S600 V12 Bi Turbo)

View attachment 421264

This car can go down to an indicated 4.5mpg on certain cold town trips / traffic to Tesco etc. Never goes above about 15mpg on long trips. There is no replacement for displacement though.

A long trip over hills 9.2mpg over 69 miles

View attachment 421266

There is an argument that with the high cost of petrol & diesel, you should make sure you enjoy burning it...

 

[dave h 2]

As mentioned in another thread, I’ve swapped the Disco 4 for a 2018 Volvo V40 T3 petrol, 34,000 miles.

It’s getting the same usage, and is also an automatic, but is only doing 31.6 mpg. We got nearly that in the 3 tonne, 3L Disco. This car is half the weight and has half the engine, and is eight years newer. It’s almost bad enough to consider rejecting the car, since making the swap was mainly to reduce running costs.

I’ve checked brake discs with the infrared thermometer after a run, and they’re all under 30*C. Will check tyre pressures. Other than looking at fuel trims/MAF/MAP etc, is this to be expected from a modern car?

Assuming you don't use cruise control and accept that frugal and Volvo have never been used in the same sentence before.
Check the plugs. If they are NGK you may find brown streaks up the insulators, if so they are toast. Try original equipment plugs, or who ever supplied the engine to Volvo which may be cheaper. Pricey I know, but I took streaky NGK's out of a ford v6 cougar that wouldn't go over 30mpg on the motorway and replaced them with ford and got 37mpg.

 

[premmington]

Fair point, it’s micro plastics (which are now in clouds) if the newspapers are to be believed that personally bothers me more than anything that escapes a diesel particulate filter. As long as it accelerates with a reasonable shove and doesn’t need plugged in to refuel it I’ll drive it.

I also agree with your point about micro plastics in the air/sea/clouds/food chain.

 

[dobbslc]

All my micro plastics are still in my 26 year old Toyota Surf, I'll not be adding to the problem by buying a new unreliable sxxxbox disposable car

I think Greta should come over and give me a massive hug!

 

[prepman]

That's about right for the model/engine in urban traffic - you also need to drive it like a petrol, not a diesel - higher revs are not a bad thing with a petrol, also use the throttle more granularly than you would a diesel. The quality of fuel will also make a minor difference but add-up over the month. different (diesel) vehicle, but I get ~36mpg on a run (just done 380 miles over a couple of days fully loaded) but ~17mpg on the weekday commute, same driving style, no traffic light drag races.

Having just moved over to a Hilux 69 reg 2.4L with Adblue etc....I was disappointed with engine performance at low revs. One staggering thing is that it's BHP is quoted at 3,500rpm which is very petrol'ly to me. The gear ratios don't make sense on a 6 speed box....in fact the handbook only qoutes 5 gears. In my estimation 6th is basically unuseable,except at 130mph or some such. Driving with eco mode and a glass of water on bonnet only returns ~ 36mpg. At 60mph in 3rd is about 2,500 rpm (recheck). The Kuga at 2L was a grunter at 2,500 and returning 43 avg mpg without light feet. Towed well at 26mpg
Kuga 2L AWD = 161 BHP @ ?rpm
Hilux 2.4L 4WD = 141 BHP @ 3,500rpm

 

[Ubique]

Power & torque are different, power is usually up towards the limiter whereas torque is much lower down, typically 1900 - 2500rpm dependent upon engine.
2.0 TDCi is 132kW @3500rpm, 400Nm @2250rpm. In theory - and mainly in practice, keeping the revs in the 2000-2500 range will give you maximum fuel economy.
Never really had much to do with Hilux's other than blowing them out from under the Taliban.... acceleration was quite good at that point.

 

[dobbslc]

Never really had much to do with Hilux's other than blowing them out from under the Taliban

I have mixed emotions about that sentence, such a waste of Hilux parts.