multieddie
New member
Just returned from a weekend in Warwick driving 5 up on the motorway at around 70mph - returned 46mpg according to the computer. Happy with that...
Technical Accuracy of MPG readout
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Technical Accuracy of MPG readout
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those with diesel who have poor mpg, might be worth disconnecting the MAF sensor temporarily to see if the Mpg improves. It seems like there are a lot of overfuelling MAFs out there.
If MAF working well, mpg should be slightly worse if disconnected.
If overfuelling, it will improve - indicating it needs changing.
I'm not sure of the type of MAF on the JTD, but on other cars the thin wire can be carefully cleaned with spray alcohol. But people like Roverron (see tuning diesels.com) advocate that mafs may be effectively a service item with a 50k ish life.
If MAF working well, mpg should be slightly worse if disconnected.
If overfuelling, it will improve - indicating it needs changing.
I'm not sure of the type of MAF on the JTD, but on other cars the thin wire can be carefully cleaned with spray alcohol. But people like Roverron (see tuning diesels.com) advocate that mafs may be effectively a service item with a 50k ish life.
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and another thing!
after reading this through again, there MUST be some way the dash computer can be accessed manually to apply a correction factor. This was a common procedure with the Rover 75/ZT after people found out the buttons one needed to push to get the dash readout!
Someone somewhere must have access to the procedures for doing this in the workshop?
after reading this through again, there MUST be some way the dash computer can be accessed manually to apply a correction factor. This was a common procedure with the Rover 75/ZT after people found out the buttons one needed to push to get the dash readout!
Someone somewhere must have access to the procedures for doing this in the workshop?
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05 plate 83k JTD
first brimful test - 51.2mpg; computer reading 39.7
(previous reading had been 37.5 over 1700 miles, so say 48mpg-ish actual)
first brimful test - 51.2mpg; computer reading 39.7
(previous reading had been 37.5 over 1700 miles, so say 48mpg-ish actual)
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well - seems to bear no relation to reality!
second fill - 40.6 on dial - 46.85 actual
third fill -42.5 on dial - 42.3 actual
second fill - 40.6 on dial - 46.85 actual
third fill -42.5 on dial - 42.3 actual
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and latest: 37.6 on computer - 48.37 actual ! I wish I could stop pressing the computer buttons, but its too addictive - like have a joke a day on the calendar.
I was thinking about this the other day on a particularly boring trip up the M40 (Beaconsfield to Leamington Spa).
I was checking my odometer reading against the mile markers.
It was clocking up a mile (on the odometer reading) against approx 1.3-1.4 miles travelled (according to the mile markers), so seriously under-reading the mileage done!
I didn't have anyone with me unfortunately, otherwise I would have slowed to 60 (indicated) and timed the period between the markers to check the speedo reading.
So, if the computer is 'seeing' less miles than it's actually doing, then the MPG calculation will be low.
I was checking my odometer reading against the mile markers.
It was clocking up a mile (on the odometer reading) against approx 1.3-1.4 miles travelled (according to the mile markers), so seriously under-reading the mileage done!
I didn't have anyone with me unfortunately, otherwise I would have slowed to 60 (indicated) and timed the period between the markers to check the speedo reading.
So, if the computer is 'seeing' less miles than it's actually doing, then the MPG calculation will be low.
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err... so does that mean we are servicing our cars too regularly and selling them too early too?! (i.e. does the total mileage shown link to what you have seen - presumably yes!)
Actually it's the other way round .
It's doing more mileage than it's showing on the odometer (in my case anyway.
E.g. Mine is only showing 1 mile for every 1.3 or so actually travelled.
That is if we can assume the Motorway markers are accurate of course, I'd think they should/would be.
I'm going to check it again when I get the chance, on another stretch of a different Motorway.
.It's doing more mileage than it's showing on the odometer (in my case anyway.
E.g. Mine is only showing 1 mile for every 1.3 or so actually travelled.
That is if we can assume the Motorway markers are accurate of course, I'd think they should/would be.
I'm going to check it again when I get the chance, on another stretch of a different Motorway.
taxiadam
New member
Guys I can tell you the marker posts your talking about on the motorway are actually every kilometre and the orange sos phones are every mile.
That would make more sense to the readings, and make them more accurate.
I tried it again last night on the way to work, only got one brief shot at it due to roadworks (no markers visible), and it was nearer 1.5-1.6 on the markers as near as I could make out.
So that scuppers my theory
I tried it again last night on the way to work, only got one brief shot at it due to roadworks (no markers visible), and it was nearer 1.5-1.6 on the markers as near as I could make out.
So that scuppers my theory
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quite funny though - we could have had a law suit to present to Fiat from hundreds of members...I still think there must be some arcane way of pressing buttons to enable calibration of the trip computer, like on the Rover 75
When I drove to London City Airport, last week, AA Route Finder reckoned it would be 160 miles, and the odometer measured 167 miles. I think I kept to their route, but it would be no surprise if I travelled slightly further, so I think it's reasonably accurate (at least within 5%).
Hello, my first post here on Fiat.
I bought a 2001 Multipla jtd earlier this year (needed 6 seats right!!) and am not impressed with the fuel consumption.
I ALWAYS get 36mpg.
I've had a full service and do mostly town driving with a 100mile motorway run every couple of weeks.
I've even tried bio-diesel in the hope it will clean injectors etc but still exactly 36mpg.
One tankfull I specifically drove very slowly at 55 on the motorway, 36mpg
Next tank I thrashed it a bit and gave it some beans on the motorway, 36mpg!!
I'm used to Audi tdi's giving me in the late 40's.
I have no computer on board, just the good old brim to brim method, and yes there are 4.5l/gal.
Please can somebody help?
I bought a 2001 Multipla jtd earlier this year (needed 6 seats right!!) and am not impressed with the fuel consumption.
I ALWAYS get 36mpg.
I've had a full service and do mostly town driving with a 100mile motorway run every couple of weeks.
I've even tried bio-diesel in the hope it will clean injectors etc but still exactly 36mpg.
One tankfull I specifically drove very slowly at 55 on the motorway, 36mpg
Next tank I thrashed it a bit and gave it some beans on the motorway, 36mpg!!
I'm used to Audi tdi's giving me in the late 40's.
I have no computer on board, just the good old brim to brim method, and yes there are 4.5l/gal.
Please can somebody help?
taxiadam
New member
As of 13th December 09 I have owned my 1.9elx 2000 Multi for one year. I have kept ALL reciepts for ALL costs that have happened in this year. In all the vehicle has cost me £6179.85 for the year. I won't list all the costs (parts, cleaning products, repairs, roof rails, bike rack etc) but some of them are below
£1750 Purchase price
£496.96 Insurance
£53 MOT only
£209 Road tax
£65 Breakdown cover
£240.10 Cam belt + ancillary belt
£1801.89 Fuel
As this is a MPG thread i'll give you those figures.
15752 miles in one year
£1801.89 fuel cost
1854.08 litres of fuel
407.84 gallons
38.62 MPG
A little geeky but not hard to do really, just a ring binder with plastic wallets and each reciept goes in there.
£1750 Purchase price
£496.96 Insurance
£53 MOT only
£209 Road tax
£65 Breakdown cover
£240.10 Cam belt + ancillary belt
£1801.89 Fuel
As this is a MPG thread i'll give you those figures.
15752 miles in one year
£1801.89 fuel cost
1854.08 litres of fuel
407.84 gallons
38.62 MPG
A little geeky but not hard to do really, just a ring binder with plastic wallets and each reciept goes in there.
Caravadossi
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Not a Multi, but ...
55 Croma 1.9/16v 150hp
My blackbox under-reads my actual brim2brim refuels by some 3mpg.
Last 10 refuels: blackbox/actual
38.7/41.8 (347ml); 35.0/38.2 (284ml); 36.1/40.4 (317ml); 40.9/44.2 (506ml); 34.1/37.9 (322ml); 40.6/41.9 (503ml); 35.5/36.7 (330ml); 40.1/43.8 (338ml); 39.2/42.4 (338ml); 42.9/44.0 (424ml).
Average: 38.3/41.1mpg
.
Hmm.. My ownership of the Multi might be short lived if it can't do over (the currently indicated) 37mpg..
Anyone get an improvement by disconnecting / blanking off the EGR?
Neil.
Anyone get an improvement by disconnecting / blanking off the EGR?
Neil.
I get 450 miles ish from 61 litres, that's 33.2 mpg.
Very disappointed.
Initially the pipe sonnected to the egr valve was not connected, great I thought, the answer to my poor fuel consumption.
So I made sure the egr valve worked then connected it all back up.
Still get 33mpg.
Rubbish.
Can anyone help???
Very disappointed.
Initially the pipe sonnected to the egr valve was not connected, great I thought, the answer to my poor fuel consumption.
So I made sure the egr valve worked then connected it all back up.
Still get 33mpg.
Rubbish.
Can anyone help???
taxiadam
New member
A recent trip to The Lake District meant I had 4 people, 4 boats and 3 bikes all on or in the Multi. They also had luggage. In all 440 miles, 55 litres, 36mpg approx.
In all
In all
