Can anyone help me with a faulty petrol gauge on a 2 Litre GTV, year 2000 16 Valve My garage says there is no diagnostic test. There solution appears to be to change parts until they find the problem, £300 so far and possibly in excess of £800.00 . I cannot believe that there is not some electrical or other test to identify if it is the sender or the gauge or some other fault.
A simple volt meter on the floating element's return wires will show you the resistance of the device, and this should vary as the unit is moved up and down.
How about asking that they do a swap of the components from another known working car?
This may be my second reply my first disapered whilst typing
When the tank is full the gauge goes stright to full It seems to behave until it reaches just below three quarters where it stays.
Some times on switching on the nedel will move to about a third full. It will gradually move up with the petrol warning light coming on at just under half full. The light goes out just after half full and the needle continues to climb to just under three quarters full. This sympton does not appear to hapen if the tank is full.
My local dealer first traced the fault to the sender which because it is attached to the pump also requires the pump to be replaced, hence a cost of £300. This did not solve the problem. The dealer now tells me that there is no diagnostic test (how he decided it was the sender in the first place he has not explained yet) and has sugested that the fault may be the gauge itself. A circa £500 job as it comes in a cluster with the other gauges. I find it difficult to believe that the only way of finding the fault appears to replace parts until the problem dissappears, and there are not some simple tests that could be done