Am only getting 11mpg on gas and thats fine, its only because the fuel gauge drops while on gas and I smelt petrol so looked deeper in to it.

I found mine round the back axle area, it was damp and stunk, it got worse very quick and I could soon see a drip.

Am replacing the broken pipe with a flexi fuel pipe and couplers.

I've put a switch inline where the fuse so I can turn the pump off to stop petrol flowing when on gas.
 
A few years ago I had an Audi A8 4.2 Quattro

I absolutely loved it but it had to go when I worked out I was getting 8mpg on the drive to work and 5mpg at weekends :crazy_driver:

That was when petrol was 80p a litre , I couldn't run a v8 as an everyday car

I've got a jaguar XKR now but it's not as bad as the Audi , 20 round town and up to 30 if you're careful
 
My 4.0 is a manual and does 17-18mpg doing local runs,never been further afield unless towing pikey box so don't know how it would far on a decent run solo.
 
My 3.9 V8 gets 5.5 miles / litre so that's 25p per mile on bendy lake district roads. It's prone to going off though if you don't keep on top of things - servicing, cleaning stepper motor, checking for vacuum leaks etc. there's always something going off!
 
My 3.9 Disco used to average around 15mpg or 8-9mpg on LPG - it was an early OMVL 'spray & pray' rather than sequential injection. Recently switched for a 4.6 HSE P38 with a sequential LPG and I've pretty much HALVED my fuel bill! (no comments please on repair costs! :D)

The addition of a trip computer shows that my average speed is just 13mph on my daily run however and hilly urban terrain to make matters worse. I've worked out that I'm getting approx 15mpg on LPG - even at that poor average speed. (Both vehicles auto boxes). Not done enough miles on petrol yet to determine mpg, but needle has barely moved in last 480 miles as it switches to LPG within 200 yards of leaving home.
 

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