28mpg :(

NikTheGeek · 14th February 2009, 09:01

I've done the brim to brim method twice now and I'm getting 28mpg from my 2l diesel.

That seems very poor compared to others. But the car seems to drive ok and I do have a working FBH which gets it up to temperature pretty quickly, but also I run the FBH for 25 mins every day too to warm the car. Do they take a lot of fuel?

Driving is typically 24 miles a day of A road driving, half clear and then as I approach Warrington, half stop/start.

Anyway, 28mph. Any ideas/comments?

tnx

Nick

Ian V · 14th February 2009, 13:12

Quote:

Originally Posted by NikTheGeek

I've done the brim to brim method twice now and I'm getting 28mpg from my 2l diesel.

That seems very poor compared to others. But the car seems to drive ok and I do have a working FBH which gets it up to temperature pretty quickly, but also I run the FBH for 25 mins every day too to warm the car. Do they take a lot of fuel?

Driving is typically 24 miles a day of A road driving, half clear and then as I approach Warrington, half stop/start.

Anyway, 28mph. Any ideas/comments?

tnx

Nick

Mine is a 2L Diesel 115BHP. I8 Miles to work and back. On A Roads 45MPG.About 50MPG on a run. I have no FBH Just a thick Jumper.

curriemart · 14th February 2009, 16:00

My cdti is only doing about 28mpg recently due to the cold weather and my journey is only about 4 miles.
In the summer that increases to about 32mpg.
On a long run down the motorway - steady 70+ - I get about 47-49mpg.
I think recently with the very cold weather the mpg has decreased significantly!
The fbh (i've just fitted one today) only uses about 0.5l / hour when running so it it isn't much and what you lose in diesel using the fbh you probably gain by starting up a warmish engine.

mossey · 16th February 2009, 10:28

Wow and I thought mine was bad because I have only been averaging 36mpg, I have even turned down my synergy and turned off the maf section to see if that helps.
I was also considering a free flow filter and doing another oil change but will see what results I get this time first.
If you find a solution I'm sure everyone would be interested to hear.

Jules · 16th February 2009, 10:44

Try running 10W40 Semi Synth oil in the winter (it's thinner than 15/40 Mineral)
We're getting 44 MPG on a daily 7 mile commuting trip.
FBH used 20 mins a day.
(I did some calculations on FBH fuel usage on another thread somewhere last year. IIRC it was a One Twelfth of a gallon for 20 mins a day & 1/8th of a gallon for 30 mins)

The FBH itself uses more than that but the overall tank to tank fuel usage is very little extra as of course you are not starting/driving on a cold engine.
Hope that makes sense.

Car is Mrs Jule's standard CDTi 131 BTW.
Nik change you MAF & replace PCV filter to start with!

NikTheGeek · 16th February 2009, 11:22

Quote:

Originally Posted by Jules

Nik change you MAF & replace PCV filter to start with!

Hmmm. I was thinking MAF. But my acceleration is fine and it will red line if I rev it hard thus indicating the MAF is ok... or disconnected... but if disconnected, wouldn't I get an engine warning light?

What is a PCV filter? I may have found the answer before anyone tells me...

Nick

Ian V · 16th February 2009, 11:29

Quote:

Originally Posted by NikTheGeek

Hmmm. I was thinking MAF. But my acceleration is fine and it will red line if I rev it hard thus indicating the MAF is ok... or disconnected... but if disconnected, wouldn't I get an engine warning light?

What is a PCV filter? I may have found the answer before anyone tells me...

Nick

Here PCV Valve - Changing in pics

Jules · 16th February 2009, 12:17

PCV ......Positive Crankcase Venting

pshuttle · 17th February 2009, 15:58

Nick,

I too am only getting around 30 MPG out of my 2.0 CDT. I have replaced the PCV filter as mentioned above and have a new airfilter, oil change and filter and fuel filter, a RoverRon MAFAM with Pierburgh MAF and a PSI Powerbox Digital tuning box. This fuel consumption seems very poor.

I removed the Powerbox for a month last year and the car was sloooow and also the fuel economy did not improve. Unplugging the MAF did not improve fuel economy.

I have read every post regarding this issue with interest but nothing suggested seems to work.

It is a shame really as I do not see why there should be such a massive variation in MPG between vehicles.

Pete

Raistlin · 17th February 2009, 16:19

I get 28 - 30 at this time of year doing 18 miles per day going to work.

For a diesel with re-map, Synergy and auto transmission I think that's not too bad.

Fuel consumption gets a little better in Summer on routine journeys and goes up to an easy 50 mpg on steady long distance driving.

14th February 2009, 09:01	#1
NikTheGeek Gets stuck in 2002 Range Rover P38 Join Date: Dec 2008 Location: Wigan Posts: 593 Thanks: 0 Thanked 0 Times in 0 Posts	28mpg :( I've done the brim to brim method twice now and I'm getting 28mpg from my 2l diesel. That seems very poor compared to others. But the car seems to drive ok and I do have a working FBH which gets it up to temperature pretty quickly, but also I run the FBH for 25 mins every day too to warm the car. Do they take a lot of fuel? Driving is typically 24 miles a day of A road driving, half clear and then as I approach Warrington, half stop/start. Anyway, 28mph. Any ideas/comments? tnx Nick

16th February 2009, 10:44	#5
Jules This is my second home ZT 260 SE Twilight and 10 other 75 ZT's :O Join Date: Jan 2007 Location: Conwy NORTH WALES Posts: 11,094 Thanks: 512 Thanked 1,116 Times in 763 Posts	Try running 10W40 Semi Synth oil in the winter (it's thinner than 15/40 Mineral) We're getting 44 MPG on a daily 7 mile commuting trip. FBH used 20 mins a day. (I did some calculations on FBH fuel usage on another thread somewhere last year. IIRC it was a One Twelfth of a gallon for 20 mins a day & 1/8th of a gallon for 30 mins) The FBH itself uses more than that but the overall tank to tank fuel usage is very little extra as of course you are not starting/driving on a cold engine. Hope that makes sense. Car is Mrs Jule's standard CDTi 131 BTW. Nik change you MAF & replace PCV filter to start with! __________________ [SIGPIC][/SIGPIC] Newbies do now!! 1. Plenum drains..all 3 or 4 year dependent 2. Cooling fan..All speeds functioning 3. Bonnet cable divider block

16th February 2009, 12:17	#8
Jules This is my second home ZT 260 SE Twilight and 10 other 75 ZT's :O Join Date: Jan 2007 Location: Conwy NORTH WALES Posts: 11,094 Thanks: 512 Thanked 1,116 Times in 763 Posts	PCV ......Positive Crankcase Venting __________________ [SIGPIC][/SIGPIC] Newbies do now!! 1. Plenum drains..all 3 or 4 year dependent 2. Cooling fan..All speeds functioning 3. Bonnet cable divider block

17th February 2009, 15:58	#9
pshuttle Avid contributor BMW G20 320d. Previously, Rover 75 2.0 CDT Club SE and CDT Classic Join Date: Dec 2006 Location: Preston Posts: 203 Thanks: 0 Thanked 0 Times in 0 Posts	Nick, I too am only getting around 30 MPG out of my 2.0 CDT. I have replaced the PCV filter as mentioned above and have a new airfilter, oil change and filter and fuel filter, a RoverRon MAFAM with Pierburgh MAF and a PSI Powerbox Digital tuning box. This fuel consumption seems very poor. I removed the Powerbox for a month last year and the car was sloooow and also the fuel economy did not improve. Unplugging the MAF did not improve fuel economy. I have read every post regarding this issue with interest but nothing suggested seems to work. It is a shame really as I do not see why there should be such a massive variation in MPG between vehicles. Pete __________________ pshuttle - Rover 75 2.0 CDT Club SE -----------------------------------------------------------

14th February 2009, 16:00	#3
curriemart Regular poster Rover 75 Join Date: Jun 2008 Location: Ed Posts: 71 Thanks: 0 Thanked 6 Times in 3 Posts	My cdti is only doing about 28mpg recently due to the cold weather and my journey is only about 4 miles. In the summer that increases to about 32mpg. On a long run down the motorway - steady 70+ - I get about 47-49mpg. I think recently with the very cold weather the mpg has decreased significantly! The fbh (i've just fitted one today) only uses about 0.5l / hour when running so it it isn't much and what you lose in diesel using the fbh you probably gain by starting up a warmish engine.

16th February 2009, 10:28	#4
mossey Regular poster Rover 75 tourer cdt Join Date: Nov 2008 Location: sheffield Posts: 89 Thanks: 0 Thanked 0 Times in 0 Posts	Wow and I thought mine was bad because I have only been averaging 36mpg, I have even turned down my synergy and turned off the maf section to see if that helps. I was also considering a free flow filter and doing another oil change but will see what results I get this time first. If you find a solution I'm sure everyone would be interested to hear.

17th February 2009, 16:19	#10
Raistlin Banned 75 CDT Connoisseur SE Auto Join Date: Nov 2006 Location: Wolverhampton Posts: 8,450 Thanks: 0 Thanked 3 Times in 3 Posts	I get 28 - 30 at this time of year doing 18 miles per day going to work. For a diesel with re-map, Synergy and auto transmission I think that's not too bad. Fuel consumption gets a little better in Summer on routine journeys and goes up to an easy 50 mpg on steady long distance driving.