Is there something wrong with my mpg figure...?

Is there something wrong with my mpg figure...?

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The Seer

Original Poster:

664 posts

210 months

Saturday 21st April 2012
quotequote all
2004 5.7 VXR Monaro.

I'd like to clear this up since quite frankly it's either me or my car but somethings not right.

There's some on here which are saying 300 miles once filled up by the trip computer. Mine tells me 240, and that's the very maximum it reads. But I always find really no more than 180-200 max per tank.

And this is what really sticks in the throat, I'm seriously not driving it very hard all the time. Ok a bit of a blast on the dual carriage here and there but a majority is spent with mixed driving, a fair amount being easy driving and using 6th gear around fifty miles an hour! I'll admit I don't use it for motorway journeys. The only motorway journey I have done is when I bought the car, circa 235 miles and even then I used 6th, kept it steady between 65-80 and it used a tank and a half!

I can't figure why with driving the car easily and normally (most of the time) I'm getting such low mpg. Ten quid see's no more than twenty miles.

A very confued Monaro owner.

Tattooboy

7,946 posts

177 months

Saturday 21st April 2012
quotequote all
70 litre tank = 15 odd gallons, around town driving 18 Mpg around 270 miles tops, the joys of owning a V8 I'm afraid.

Only long motorway journeys will you see a decent mpg return frown

lastmin8264

509 posts

149 months

Saturday 21st April 2012
quotequote all
If its been properly serviced recently get it rr to check things are ok

But they do like a drink, some people post about the max range and mpg I do short journeys daily driver and get 16mpg, just done a round trip from mcr to monkfish all motorway a few hundred miles and was 26iirc and that's the best I ever saw. They are what they are, get it on a rr if the bhp is as expected then its just live with it. If bhp down you may need to start looking at faults messing up the mpg. These are not French hatches they use lots of petrol mate.

ARAF

20,759 posts

222 months

Saturday 21st April 2012
quotequote all
It may just be your driving style, or the fact that you're doing short journeys.

Edited by ARAF on Saturday 21st April 00:19

leigh1050

2,372 posts

164 months

Saturday 21st April 2012
quotequote all
At Spa we was getting 5-6 a gallonbiglaughbiglaughbiglaugh

007 VXR

64,187 posts

186 months

Saturday 21st April 2012
quotequote all
reset the trip computer and try again biggrin

The Seer

Original Poster:

664 posts

210 months

Saturday 21st April 2012
quotequote all
Tattooboy said:
70 litre tank = 15 odd gallons, around town driving 18 Mpg around 270 miles tops, the joys of owning a V8 I'm afraid.

Only long motorway journeys will you see a decent mpg return


I'm seeing 11-15 round town, plus I don't get why it took two and a half tanks to cover circa 235 miles when I drove it home on the day of purchase.

If I nailed it all the time, I'd say fair enough. It's like it's got the efficency of a classic V 8 engine.

The Seer

Original Poster:

664 posts

210 months

Saturday 21st April 2012
quotequote all
lastmin8264 said:
If its been properly serviced recently get it rr to check things are ok

But they do like a drink, some people post about the max range and mpg I do short journeys daily driver and get 16mpg, just done a round trip from mcr to monkfish all motorway a few hundred miles and was 26iirc and that's the best I ever saw. They are what they are, get it on a rr if the bhp is as expected then its just live with it. If bhp down you may need to start looking at faults messing up the mpg. These are not French hatches they use lots of petrol mate.


Yeah, was planning on visiting the dyno soon enough. Doesn't feel odd or sluggish, doesn't smell of a rich mixture. Although can be slightly smokey when at times. More of a light grey smoke than darker or black.

The Seer

Original Poster:

664 posts

210 months

Saturday 21st April 2012
quotequote all
007 VXR said:
reset the trip computer and try again


Gonna have to be, but pay day isn't for another few days and me and the car have drunk all our money already!

ARAF

20,759 posts

222 months

Saturday 21st April 2012
quotequote all
Next time you stop, check that none of the wheels is hotter than the rest.

The Seer

Original Poster:

664 posts

210 months

Saturday 21st April 2012
quotequote all
ARAF said:
Next time you stop, check that none of the wheels is hotter than the rest.


Surely I'll be able to feel if there was some hinderance from the braking system? Nothing so far has alerted me to it, no suspicous feedback etc. But yes maybe worth a go.

007 VXR

64,187 posts

186 months

Saturday 21st April 2012
quotequote all
The Seer said:
007 VXR said:
reset the trip computer and try again biggrin
Gonna have to be, but pay day isn't for another few days and me and the car have drunk all our money already!
snowwolf had this problem yes

but he had not reset the trip for over 10k miles
so no matter how slow he drove he could not get any better mpg;)

reset it and go for a motorway run.

The Seer

Original Poster:

664 posts

210 months

Saturday 21st April 2012
quotequote all
leigh1050 said:
At Spa we was getting 5-6 a gallonbiglaughbiglaughbiglaugh


On WOT my immediate MPG reads 3. I'm guessing this is perfectly normal?

007 VXR

64,187 posts

186 months

Saturday 21st April 2012
quotequote all
The Seer said:
leigh1050 said:
At Spa we was getting 5-6 a gallonbiglaughbiglaughbiglaugh
On WOT my immediate MPG reads 3. I'm guessing this is perfectly normal?
yes

mine reads 30 to 40 at 80mph smile

fildigger

1,095 posts

204 months

Saturday 21st April 2012
quotequote all
007 VXR said:
yes

mine reads 30 to 40 at 80mph smile
Dito...on the instant reading (does fluctuate a lot dependent on the merest of throttle inputs!)....had the car a week, done around 500 miles in her and averaging 25mpg (50% dual carriageway in that)

Ps. going on my local scoobies Dyno' Day this sunday....see what the BHP and AFR readings are like.smile

ARAF

20,759 posts

222 months

Saturday 21st April 2012
quotequote all
The Seer said:
ARAF said:
Next time you stop, check that none of the wheels is hotter than the rest.
Surely I'll be able to feel if there was some hinderance from the braking system? Nothing so far has alerted me to it, no suspicous feedback etc. But yes maybe worth a go.
You've got over a tonne and a half of metal and one of the torquiest engines currently fitted in a car, so don't bank on it.

V88Dicky

7,302 posts

182 months

Saturday 21st April 2012
quotequote all
The Seer said:
I'm seeing 11-15 round town, plus I don't get why it took two and a half tanks to cover circa 235 miles when I drove it home on the day I purchased it.
2.5 tanks to do 235 miles! yikes

That's over 37 gallons and <6.5 mpg

The Seer

Original Poster:

664 posts

210 months

Saturday 21st April 2012
quotequote all
V88Dicky said:
The Seer said:


I'm seeing 11-15 round town, plus I don't get why it took two and a half tanks to cover circa 235 miles when I drove it home on the day I purchased it.


2.5 tanks to do 235 miles! yikes

That's over 37 gallons and <6.5 mpg


Sorry, my mistake it was a tank and a half.

The Seer

Original Poster:

664 posts

210 months

Saturday 21st April 2012
quotequote all
007 VXR said:
The Seer said:
007 VXR said:
reset the trip computer and try again


Gonna have to be, but pay day isn't for another few days and me and the car have drunk all our money already!

snowwolf had this problem yes

but he had not reset the trip for over 10k miles
so no matter how slow he drove he could not get any better mpg

reset it and go for a motorway run.


I think this could have something to do with it. I haven't reset it and it's possible it hasn't been reset for sometime.

BlueDevil

414 posts

203 months

Saturday 21st April 2012
quotequote all
I'm averaging between 27 - 31mpg in my dd and do about a 50 mile round trip mixture of A roads and occasionally motorway, but mines a CV8 so different ratios