My car runs on LPG, so I expect the petrol gauge to drop a little as it burns petrol initially, until it can switch to LPG.
However, on occasion I have noticed the petrol gauge dropping slowly even after the car has switched to LPG. This seems very confusing as I cannot see how I can be burning petrol and LPG simultaneously,unless I am burning one fuel, and leaking the other. The gauge can drop by almost a quarter of a tank over my 65 mile commute to work. On most journeys this does not happen, just occasionally. I have given it some thought, and cannot determine any pattern as to what might cause it.
If that seems strange, what is stranger is that usually at some point, I will glance down at the petrol gauge and the needle will have returned to its original position. I am confident that I am not leaking either LPG or petrol.
I wondered if anyone else has experienced this? Not unduly worried about making a repair, unless that turns out to be cheap and simple. I am content to live with this 'feature' of my car.
Any suggestions?