Fuel loss and cat damage.

One for the experts ;-)

I am losing fuel - I'm pretty sure I'm not burning it. On a constant run
from 0 miles to 225miles I use 60/65 litres of fuel. This equates to 100
miles in the first 1/4 of the guage, 75 in the second and 50 in the third.
If I drive to a place, say 50 miles away after filling up and driving
normaly, park up overnight, start up in the morning - the guage happily
stays in the place I'd expect, until I hit the first corner/hill and it
drops and "loses" me 50 miles seemingly!

I know it's not the guage, as it's the amount of fuel I put back in that
hints that I'm losing it. Is this "normal" or is something not quite right
in there?

It's a 4.6 V8i running through a 3.9 Y-pipe with cats - which have begun to
rattle since replacement in March (OEM - £1800!?!). Can anyone tell me if
the 4.6 needed different cats?

Vehicle is a 97 Discovery.

--
Neil

By my calculations, that works out at about 17 mpg. The 'official' fuel
economy figures for a 1997 V8i Discovery [see link below] suggest around 19
mpg, so I don't think you're far off at 17. Welcome to the world of V8
engines...

[http://www.parkers.co.uk/choosing/tech_data/index.aspx?manu_name=Land+Rover
&manufacturer_name=5088&model_id=417&fueltype=&months=&spare1=&spare2=]

--> Greg

"Neil Brownlee" <[email protected]> wrote in message
news:[email protected]...
> One for the experts ;-)
>
> I am losing fuel - I'm pretty sure I'm not burning it. On a constant run
> from 0 miles to 225miles I use 60/65 litres of fuel. This equates to 100
> miles in the first 1/4 of the guage, 75 in the second and 50 in the third.
> If I drive to a place, say 50 miles away after filling up and driving
> normaly, park up overnight, start up in the morning - the guage happily
> stays in the place I'd expect, until I hit the first corner/hill and it
> drops and "loses" me 50 miles seemingly!
>
> I know it's not the guage, as it's the amount of fuel I put back in that
> hints that I'm losing it. Is this "normal" or is something not quite right
> in there?
>
> It's a 4.6 V8i running through a 3.9 Y-pipe with cats - which have begun
to
> rattle since replacement in March (OEM - £1800!?!). Can anyone tell me if
> the 4.6 needed different cats?
>
> Vehicle is a 97 Discovery.
>
> --
> Neil
>
>

On Thu, 12 Aug 2004 10:40:49 +0000 (UTC), "Neil Brownlee"
<[email protected]> wrote:

>One for the experts ;-)
>
>I am losing fuel - I'm pretty sure I'm not burning it. On a constant run
>from 0 miles to 225miles I use 60/65 litres of fuel. This equates to 100
>miles in the first 1/4 of the guage, 75 in the second and 50 in the third.
>If I drive to a place, say 50 miles away after filling up and driving
>normaly, park up overnight, start up in the morning - the guage happily
>stays in the place I'd expect, until I hit the first corner/hill and it
>drops and "loses" me 50 miles seemingly!
>
>I know it's not the guage, as it's the amount of fuel I put back in that
>hints that I'm losing it. Is this "normal" or is something not quite right
>in there?
>
>It's a 4.6 V8i running through a 3.9 Y-pipe with cats - which have begun to
>rattle since replacement in March (OEM - £1800!?!). Can anyone tell me if
>the 4.6 needed different cats?
>
>Vehicle is a 97 Discovery.

Doesn't sound too awful. Ignore the gauge - mine is hopeless, though
better than a lot of other cars. You might expect the 4.6 to be a bit
more efficient than a 3.9, but then you have a lot of other crap
(sorry, essential off road kit) bolted on. Mine does 18mpg on petrol,
a little less on gas, on standard wheels and no essential off-road kit
fitted.

As for cats, well I paid £600 for mine replacing with non-genuine ones
and I haven't noticed any major difference over OEM. If they are
rattling I'd check the fittings haven't worked loose - mine did.

If you think you have a leak, fill it to the brim and leave it a day
or too. See if you can get any more in after that. A leak is usually
obvious if it's from the tank end - in the engine bay I guess it could
just vaporise without being detectable.
--

Tim Hobbs

'58 Series 2 88" aka "Stig"
'77 101FC Ambulance aka "Burrt"
'95 Discovery V8i aka "The Disco" (FOR SALE)
'03 Volvo V70

My Landies? http://www.seriesii.co.uk
Barcoding? http://www.bartec-systems.com
Tony Luckwill web archive at http://www.luckwill.com

On Thu, 12 Aug 2004 10:40:49 +0000 (UTC), "Neil Brownlee"
<[email protected]> wrote:

>One for the experts ;-)
>
>I am losing fuel - I'm pretty sure I'm not burning it. On a constant run
>from 0 miles to 225miles I use 60/65 litres of fuel. This equates to 100
>miles in the first 1/4 of the guage, 75 in the second and 50 in the third.
>If I drive to a place, say 50 miles away after filling up and driving
>normaly, park up overnight, start up in the morning - the guage happily
>stays in the place I'd expect, until I hit the first corner/hill and it
>drops and "loses" me 50 miles seemingly!
>
>I know it's not the guage, as it's the amount of fuel I put back in that
>hints that I'm losing it. Is this "normal" or is something not quite right
>in there?
>
>It's a 4.6 V8i running through a 3.9 Y-pipe with cats - which have begun to
>rattle since replacement in March (OEM - £1800!?!). Can anyone tell me if
>the 4.6 needed different cats?
>
>Vehicle is a 97 Discovery.

Oh, meant to say...

I get 300 miles comfortably on a full tank before the yellow light
really starts to worry me. I have had 320 miles on several occasions,
and once I managed 340 miles in the depths of Lincolnshire, which
apparently is served by only 3 petrol stations, 2 of which are closed
down. It was a brown trouser moment really, due to the 8 and a half
month pregnant missus getting more than slightly stressed and we all
know what that can bring on!




--

Tim Hobbs

'58 Series 2 88" aka "Stig"
'77 101FC Ambulance aka "Burrt"
'95 Discovery V8i aka "The Disco" (FOR SALE)
'03 Volvo V70

My Landies? http://www.seriesii.co.uk
Barcoding? http://www.bartec-systems.com
Tony Luckwill web archive at http://www.luckwill.com

By my calculations, that works out at about 17 mpg. The 'official' fuel
economy figures for a 1997 V8i Discovery [see link below] suggest around 19
mpg, so I don't think you're far off at 17. Welcome to the world of V8
engines...

[http://www.parkers.co.uk/choosing/tech_data/index.aspx?manu_name=Land+Rover
&manufacturer_name=5088&model_id=417&fueltype=&months=&spare1=&spare2=]

--> Greg

"Neil Brownlee" <[email protected]> wrote in message
news:[email protected]...
> One for the experts ;-)
>
> I am losing fuel - I'm pretty sure I'm not burning it. On a constant run
> from 0 miles to 225miles I use 60/65 litres of fuel. This equates to 100
> miles in the first 1/4 of the guage, 75 in the second and 50 in the third.
> If I drive to a place, say 50 miles away after filling up and driving
> normaly, park up overnight, start up in the morning - the guage happily
> stays in the place I'd expect, until I hit the first corner/hill and it
> drops and "loses" me 50 miles seemingly!
>
> I know it's not the guage, as it's the amount of fuel I put back in that
> hints that I'm losing it. Is this "normal" or is something not quite right
> in there?
>
> It's a 4.6 V8i running through a 3.9 Y-pipe with cats - which have begun
to
> rattle since replacement in March (OEM - £1800!?!). Can anyone tell me if
> the 4.6 needed different cats?
>
> Vehicle is a 97 Discovery.
>
> --
> Neil
>
>

On Thu, 12 Aug 2004 10:40:49 +0000 (UTC), "Neil Brownlee"
<[email protected]> wrote:

>One for the experts ;-)
>
>I am losing fuel - I'm pretty sure I'm not burning it. On a constant run
>from 0 miles to 225miles I use 60/65 litres of fuel. This equates to 100
>miles in the first 1/4 of the guage, 75 in the second and 50 in the third.
>If I drive to a place, say 50 miles away after filling up and driving
>normaly, park up overnight, start up in the morning - the guage happily
>stays in the place I'd expect, until I hit the first corner/hill and it
>drops and "loses" me 50 miles seemingly!
>
>I know it's not the guage, as it's the amount of fuel I put back in that
>hints that I'm losing it. Is this "normal" or is something not quite right
>in there?
>
>It's a 4.6 V8i running through a 3.9 Y-pipe with cats - which have begun to
>rattle since replacement in March (OEM - £1800!?!). Can anyone tell me if
>the 4.6 needed different cats?
>
>Vehicle is a 97 Discovery.

Doesn't sound too awful. Ignore the gauge - mine is hopeless, though
better than a lot of other cars. You might expect the 4.6 to be a bit
more efficient than a 3.9, but then you have a lot of other crap
(sorry, essential off road kit) bolted on. Mine does 18mpg on petrol,
a little less on gas, on standard wheels and no essential off-road kit
fitted.

As for cats, well I paid £600 for mine replacing with non-genuine ones
and I haven't noticed any major difference over OEM. If they are
rattling I'd check the fittings haven't worked loose - mine did.

If you think you have a leak, fill it to the brim and leave it a day
or too. See if you can get any more in after that. A leak is usually
obvious if it's from the tank end - in the engine bay I guess it could
just vaporise without being detectable.
--

Tim Hobbs

'58 Series 2 88" aka "Stig"
'77 101FC Ambulance aka "Burrt"
'95 Discovery V8i aka "The Disco" (FOR SALE)
'03 Volvo V70

My Landies? http://www.seriesii.co.uk
Barcoding? http://www.bartec-systems.com
Tony Luckwill web archive at http://www.luckwill.com