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[tango]

hi guys
wondering if anyone can help me
i recently had my car converted to lpg
it was giving me around 20mpg on petrol so it was around 40 miles to a tenner

after my gas install
i got a 100 litre tank and get around 85-90 litres of gas in it
this cost just under 50 quid
but the problem is im only getting around 250 miles of that tank of gas
surely this cant be right
ive been back to the gas guy and he said all is well and cant suss out why so less miles
my question from those of you who have had thier cars converted how accuarate is your trip computer on gas
for example
i get around 85-90 litres of gas in my tank
so this is around 20 gallons
but my trip computer shows that ive only used around 12 gallons and then the gas is finished


thanks in advance

[Entwood]

If you have a 100 litre tank, you should only get 80 litres in .. they only fill to 80% for safety.

80 litres is 17.62 gallons ... so 250 miles is 14 mpg on gas. I would expect around 16 mpg if you averaged 20mpg on petrol, so that is fairly close.

 20 mpg is around 4.4 m/litre so at 1.18 p/litre is about 27 pence /mile on petrol

14 mpg is around 3.08 m/litre so at .60 p/litre is about 19.5 pence /mile on LPG

so you are saving about 8 pence /mile on LPG.

Now my averages are quite a bit higher than yours .. but style of driving, terrain etc etc all make a large difference.

Your on-board computer may wel be like mine .... it still thinks it is running on petrol !!! I ignore it and use the odometer. That is reset every LPG fill and I have 3 "ranges" that tell me when I need to refill ..

Towing : 180 miles
Solo around Town : 240 miles
Solo on a long run : 300 miles

mines an 80 ltr tank .. so I get 64 litres in on a good day ..

[Kevin Wood]

I'd agree that overall fuel consumption on petrol and gas sounds high on your car. This depends on the type of driving that you normally do, though. It might be reasonable for city driving and short journeys but if that driving includes significant amounts of cruising I would say you might have a problem.

Firstly, though, ignore what the trip computer says. It is based on the fuel delivery of the petrol system and what it reads when on LPG depends how accurately the system has been calibrated.

I also have an 80l tank and get between 270 and 300 miles to a tank of mixed driving - on a 3.2 auto.

Note that LPG pumps compensate for temperature so the volume in litres can vary significantly between fillups. Try noting litres and mileage over a couple of tanks and work out what you're getting to a gallon of LPG.

Kevin

[tunnie]

90L tank here, its not set quite right i only get 66L in, but that gets me 350 miles

[Entwood]

90L tank here, its not set quite right i only get 66L in, but that gets me 350 miles

but only 2/3 rds of an engine and I believe it's never gone above 2000 rpm ??

 

[tunnie]

90L tank here, its not set quite right i only get 66L in, but that gets me 350 miles

but only 2/3 rds of an engine and I believe it's never gone above 2000 rpm ??

 

normal cruise is 80mph on motorway so 3.2k rpm! 

[PhilRich]

90L tank here, its not set quite right i only get 66L in, but that gets me 350 miles

but only 2/3 rds of an engine and I believe it's never gone above 2000 rpm ??

 

Ah yes, but isn't 2/3rds working better than 3/3rds busted?

[tunnie]

90L tank here, its not set quite right i only get 66L in, but that gets me 350 miles

but only 2/3 rds of an engine and I believe it's never gone above 2000 rpm ??

 

Ah yes, but isn't 2/3rds working better than 3/3rds busted?

   

[Lazydocker]

Firstly, your tank is overfilling and this is dangerous. Not too bad in the winter but in summer time this is more crucial.

Secondly... Give us a clue as to the style of driving and type, i.e. Heavy foot? Town/cruising?

I'd say all your figures seem a little low but not excessively

[tango]

hi
thanks for replies guys
the car is a 2.6 v6 auto
the main milaege is local
i do have a heavy foot sometimes as i like to have a bit of fun
however like i said before i was getting around 40 miles to tenner on petrol and im only getting max 250miles out of a full tank of gas this is just under 50 quid as its costing 56p a litre at the moment
so basically ive had a gas conversion just to get an extra 50miles out of 50quids worth of fuel
this cant be right
also my engine management light is currently on
before the gas conversion i was getting code 0430
but after the gas conversion im getting 0170,0173 and still the 0430
do you think this is affecting the consumption

[feeutfo]

quite possibly, pre cat code isnt much to worry about but fuel trim malfunction codes need attention, usually air leak or maf most likely, wondering if its been put back together right...?

[Kevin Wood]

quite possibly, pre cat code isnt much to worry about but fuel trim malfunction codes need attention, usually air leak or maf most likely, wondering if its been put back together right...?

Yep, sounds like the LPG system is poorly calibrated, or MAF / air leak problem if it's giving fuel trim codes.

Kevin

[Damian (damian0708 OKP)]

I have Omega 2,5 V6 with LPG, I have cylinder 50L and I tank 48L because I don't have protection.

On 48L I can drive 200miles, but in Poland we have worse LPG.

Sorry my english is not good but I learning

The best LPG instalation for Omega V6 is STAG or Prins

[tango]

as far as i can see all looks well and fitted correctly
is their anyone local to me in birmingham with a proper tech 2 that can have a look
i dont mind paying them for the trouble