I converted my TJ over to dual fuel last week and ever since then i have been getting incorrect readings on the trip computer. For example i have a full tank of petrol and very little gas yet the trip computer indicates while i am driving on petrol that i only have 150km's left in the petrol tank which would be correct if i was driving on gas but i am on petrol. The other anomaly is that if you are driving on gas or petrol the average fuel consumption being shown is in the mid 40 litres per 100kms. Has anybody experienced this or know of the problem as the installer does not know what the problem is. The fuel gauge is used for both petrol and gas.
Thanks in anticipation!

where i used to work the work wangons magnas on gas the trip computers functions were just that the fuel usage and distance to empty etc... were made redundant...

i dont think there is an interface so the ecu can i identify if it's using gas/petrol and the basic functions are lost...

but the trip meter odo still works

you will just have to go by the fuel gauge and work out you distance to empty and consumption the old way

The fuel gauge is used for both petrol and gas.
Thanks in anticipation!

I thought you need a gauge for gas only?Your trip computer is set up for petrol,is it not?
Maybe the computer is for fluid only.

I converted my TJ over to dual fuel last week and ever since then i have been getting incorrect readings on the trip computer. For example i have a full tank of petrol and very little gas yet the trip computer indicates while i am driving on petrol that i only have 150km's left in the petrol tank which would be correct if i was driving on gas but i am on petrol. The other anomaly is that if you are driving on gas or petrol the average fuel consumption being shown is in the mid 40 litres per 100kms. Has anybody experienced this or know of the problem as the installer does not know what the problem is. The fuel gauge is used for both petrol and gas.
Thanks in anticipation!


I've got the same problem on our TJ Sports...
Now I just go off my gas fuel guage.
Even when you use gas, the trip computer thinks ur using the petrol as opposed to the gas and keep calculating that way. Which I had a gut feeling it would do - I did like my "Range to Empty" reading...

How is ur economy by the way?
Im suprised, I've done 150km, and my gas guage still indicates a full 4 bars :confused:

*edit*
I just read that ur guage works for both fuels? How the hell does that work???

My LPG set up uses the original gauge and just changes as I switch over from LPG to Petrol or visa versa. The trip computer is stuffed on LPG, I think it adds about 4-5 to the figures it is so hard to figure out so I gave up.

It still works well on Petrol, we went on a trip last weekend and ran the car on premium unleaded and the trip computer was spot on.

Losing the trip computer on LPG is a small price to pay for the savings.

where i used to work the work wangons magnas on gas the trip computers functions were just that the fuel usage and distance to empty etc... were made redundant...

i dont think there is an interface so the ecu can i identify if it's using gas/petrol and the basic functions are lost...

but the trip meter odo still works

you will just have to go by the fuel gauge and work out you distance to empty and consumption the old way

OK thanks Andrew for making a reply.
But one thing is the service book does say that the trip computer will work for either fuel !

I thought you need a gauge for gas only?Your trip computer is set up for petrol,is it not?
Maybe the computer is for fluid only.

No the current fuel gauge somehow will read both fuels and the service book says that the trip computer will read and register for both fuels.

I've got the same problem on our TJ Sports...
Now I just go off my gas fuel guage.
Even when you use gas, the trip computer thinks ur using the petrol as opposed to the gas and keep calculating that way. Which I had a gut feeling it would do - I did like my "Range to Empty" reading...

How is ur economy by the way?
Im suprised, I've done 150km, and my gas guage still indicates a full 4 bars :confused:

*edit*
I just read that ur guage works for both fuels? How the hell does that work???

Thanks for your reply. Yes well my range to empty does not matter whether i have a full tank of gas or petrol it will always show about 160kms to empty. Even when i am using gas the average fuel consumption being used is something like 40 odd km's per litre per 100km's as opposed to about 11-12 while on petrol so the trip computer is giving me a different reading to what it shows me on petrol. As i had a bit of a mixed driving between petrol and gas (trying to reset the computer and wait for it to adjust to the different fuel etc) i cant really give you an accurate total of km's driven for a fill total of 65 litres but i am guessing it would have been around 400-420 km's total. The service book tells me that the trip computer will work for both fuels !

My LPG set up uses the original gauge and just changes as I switch over from LPG to Petrol or visa versa. The trip computer is stuffed on LPG, I think it adds about 4-5 to the figures it is so hard to figure out so I gave up.

It still works well on Petrol, we went on a trip last weekend and ran the car on premium unleaded and the trip computer was spot on.

Losing the trip computer on LPG is a small price to pay for the savings.
Yes agree that the cost of LPG is a small price to pay for the fuel savings but the problem is me being anal and a perfectionist because the service book tells me that the trip computer will work for both fuels !

I only have the kilometres travelled & the set speed working on mine after the conversion.
I did hear of someone getting all of it working but can't remember where or who.

I only have the kilometres travelled & the set speed working on mine after the conversion.
I did hear of someone getting all of it working but can't remember where or who.

Yep that seems to be about what i have working on mine also despite the service book telling me that it will work on both fuels !

Yep that seems to be about what i have working on mine also despite the service book telling me that it will work on both fuels !


What the manual says about the trip computer working for gas and petrol ONLY applies for factory LPG cars.

I also have an aftermarket dual fuel system, and the trip computer works perfectly for petrol, but is inacurate on LPG.

For me, it doesn't bother me, I know I'm running economically on LPG, I don;t need the computer to tell me.

I agree, VRwagon, but it would be nice for it to work as well, tho'