Is there something wrong with my mpg figure...?
Discussion
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.
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 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
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.
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.
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.
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!
That's over 37 gallons and <6.5 mpg
Sorry, my mistake it was a tank and a half.
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
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.
Chaz9950 said:
Has it recently been serviced?
If not, it might be worth replacing the oils - engine, gearbox and diff, whether they 'need' it or not. Get a new set of filters too - fuel and air, and see that there's no restrictions in the air filter piping / housing. COuld be worth checking the inlet manifold too, if it's not a huge job.
If not any better, maybe get it on a diagnostic tester, and see if there are any bugs? Or maybe a rolling-road tune up?
If not, it might be worth replacing the oils - engine, gearbox and diff, whether they 'need' it or not. Get a new set of filters too - fuel and air, and see that there's no restrictions in the air filter piping / housing. COuld be worth checking the inlet manifold too, if it's not a huge job.
If not any better, maybe get it on a diagnostic tester, and see if there are any bugs? Or maybe a rolling-road tune up?
I think it'd be wise as a matter of procedure and prevention of any nasty suprises occurring.
nosubstitute said:
I used my car last week driving like Miss Daisy and got 14mpg. These cars will never give pleasing mpg figures.
Just re-set the trip computer. Used this morning for a round trip of 15 miles. Got an average of 17.5 mpg. Used 6th along relatively straight B road (9 miles of the trip, 50 mph). Rest of the mileage was round town and I did give it some beans here and there!
I think 17.5 was pretty good!
Should've reset that trip computer a while back! ringram said:
Did 280 miles yesterday, London to Keswick, 12 Gallons = 23.3mpg
Not babying it either.
My long term mileage computer on the dash is reading 24mpg at the moment, sits between that and 23mpg.
So you guys getting less must be doing loads of around town use, or as mentioned need to do some data logging.
Check out your fuel trims, o2 switching, mv readings, codes etc.
Not babying it either.
My long term mileage computer on the dash is reading 24mpg at the moment, sits between that and 23mpg.
So you guys getting less must be doing loads of around town use, or as mentioned need to do some data logging.
Check out your fuel trims, o2 switching, mv readings, codes etc.
Yeah, I do use the car for fair amount of round town usage. I donh't often see motorway journeys. Just used a pleasure ride at the weekend.
the_ferret82 said:
The Seer said:
Yeah, I do use the car for fair amount of round town usage. I donh't often see motorway journeys. Just used a pleasure ride at the weekend.
then i doubt you will see more MPG than your getting.
i have just done over 600 miles in the last 2 weeks with a mixture of motorway, A roads and B roads and returned avg 20mpg and i was not hanging around for any of those miles.
fyi that was all done on 2 full tanks only..
Pay day tomorrow means more fuel for the car. I'll reset the trip computer and record different journeys on various roads.
ringram said:
The Seer said:
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.
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.
If this is correct then something is seriously wrong either with your tune, or with perhaps your O2 sensors, exhaust leak etc.
Get it seen to!
Post cat O2 sensors have been deleted, could this be an issue?
ringram said:
The Seer said:
Post cat O2 sensors have been deleted, could this be an issue?
No, they are only there to QA cat function.
But if you are running in open loop the whole time at 12:1 AFR that would explain it.. which is why it was suggested by Mr Fish that you need to do some data logging to see if anything looks weird.
Ok, maybe this data logging may be a matter of course. It's not that expensive?
The Seer said:
ringram said:
The Seer said:
Post cat O2 sensors have been deleted, could this be an issue?
No, they are only there to QA cat function.
But if you are running in open loop the whole time at 12:1 AFR that would explain it.. which is why it was suggested by Mr Fish that you need to do some data logging to see if anything looks weird.
Ok, maybe this data logging may be a matter of course. It's not that expensive?
Yes/no?
ringram said:
Depends where you take it.
Ring around and ask. Some may do it as part of helping diag something on the basis any issue found will end up with work for them.
If you are around SE England you are welcome to pop by and Ill take a look for you to see if its anything obvious like fuel trims, o2 switching, codes etc.
Ring around and ask. Some may do it as part of helping diag something on the basis any issue found will end up with work for them.
If you are around SE England you are welcome to pop by and Ill take a look for you to see if its anything obvious like fuel trims, o2 switching, codes etc.
South East mate? I'm in Essex reasonably close to you? Many thanks for the offer, much appreciated!
The Seer said:
ringram said:
Depends where you take it.
Ring around and ask. Some may do it as part of helping diag something on the basis any issue found will end up with work for them.
If you are around SE England you are welcome to pop by and Ill take a look for you to see if its anything obvious like fuel trims, o2 switching, codes etc.
Ring around and ask. Some may do it as part of helping diag something on the basis any issue found will end up with work for them.
If you are around SE England you are welcome to pop by and Ill take a look for you to see if its anything obvious like fuel trims, o2 switching, codes etc.
South East mate? I'm in Essex reasonably close to you? Many thanks for the offer, much appreciated!
Ello?
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