C5 HDI Heavy on fuel

[imperial21]

Hi
This is one of my mosy common moans about my C5 i think the fuel consumption is poor too bad and i am very fed up with and very close to selling it and going German !

I have used my car to do 230 mile round trip then a couple of local trips, and i have almost used £50 worth of fuel i put !!
The car has just had a new genuine air flow meter, is serviced fine , wheels arent binding, I have sorted a slack throttle cable, I now know the car has some performance, but i dont drive that way i drive thinking about fuel consumption and i am light on the accelerator pedal.
The fuel computer says it was doing 50 ish on the trip which i thought was low and i wanted to see 55 mpg ish.
Has anyone ideas before i give up with it.
My car is a 2ltr Hdi which is supposed to be the good one !

[oneday]

have you tried a good fuel system cleaner

[Northern_Mike]

Yes. That doesn't sound right. I used £30 worth of fuel yesterday and did 240 miles, 212 of it in a motorway blast.. I don't have a fuel computer in mine. Normal driving with the 2.0 8v HDi 5-speed box was getting me around 46mpg, motorway at 70 nearer 55. Autobahn about 38-40 it seems..

[oneday]

i use about 22 quid a week in fuel about 200 miles mostly cold running at this time of year price of fuel £137.9 ltr. all bought at the shell station if i use tesco or the likes of i use more and the engine runs rough so i keep away from them.

[qprdude]

I get less than 45 ish on a motorway run, and about 30 ish local. I'm fairly timid with the right foot locally, but like to give the 2.2 a good run out on a long journey. Allegedly, speeds of xxx have been reached on occasion. To be honest, I researched the car thoroughly before buying so I knew what to expect. I didn't buy it for economy or I would have got a Nissan Micra! I know there are some big diesel beasts with reportedly 65 mpg+ but these figures are usually from a factory test circuit with all extra weight, including spare wheel and jack etc removed, and in windless conditions. Doubt if they are ever attainable on the road.
Afraid there is often a downside to luxury.

[Peter.N.]

There is definitly something wrong with that, I can get 60+ mpg from my 2.0. Hdi and also from my 406 Hdi. The 2.2 is notoriously bad on fuel, I struggle to get more than 40 mpg but normally 2.0. are brilliant.

As a guide it should do around 60 mpg at a steady 60 mph on a flat road.

You will have difficulty finding another vehicle of anything like that size that does better, I think the 2.0. 8 valve is one of the best diesels around.

Is the engine running at normal temperature?

Peter

[imperial21]

I cant see anything wrong with the car, No smoke, Temp half way as always, I am wondering if the car needs to go on a lexia if it might find a fault ? I always thought the HDI was great but I have never felt the fuel economy has been great in this C5, I bought the car as it was a good medium of size car and economy. I am really disappointed in the C5 since my Xantia, The xantia was better !!

[den169]

2003 hdi 2lt sx estate mine does around 53 54 on the motorway at just under 70mph can't see anyway one of these will do 60mpg unless its downhill all the way.I get around 38 knocking about.

[Peter.N.]

That sounds about right but you keep you speed down to 60 mph and revs down to around 2000 rpm I assure you they will do 6o mpg. This was coming home from Scotland last year. This was in the 406 estate - same engine.

Peter

[imperial21]

On my trip the other weekend i was like a feather on the pedal, 60mph is fine to me ! To be honest it can be hard to hold the car at 60mph and be light on the throttle pedal because as soon as i lightly press the accelerator the car is slowing rapidly.

[oneday]

fit cruise control that makes it easy

you press the accelerator and the car slows

[qprdude]

The onboard computer gives a journey usage, but it's not always accurate. Isn't the only way to get a proper reading is by filling the tank, do a measured distance, refill the tank and do the math.

[oneday]

yes i do this with mine i use a calculator i found online my computer is reading low all the time so i only use it as guidance

[den169]

Mine has cruise control on brilliant for motorways.

[oneday]

use my cruise even at 30 mph when conditions allow