Talk Morgan Forums Morgan Sports Cars Maintenance & Servicing Fuel Gauge Shows "Empty" +4 GDI

After the last filling up with petrol the fuel gauge showed some ticks below "full". Within a drive of about two hours it gradually went down to "empty" and the the built in warning light came on. A check at a petrol station showed no loss of petrol. Just the usual consumption. The DTE shows 0km and the average consumption is on 0 liters/km as well. Since then we have driven 2000km from Spain back home to Switzerland. Calculating fuel consumption manually.

It is an 2019 Plus4 traditional with 47000km on the clock. I think it is the fuel gauge sensor that belongs to the fuel pump or the signal cable that runs from there to the gauge. I can not reach the cable without removing the dashboard. Has anyone encountered the same problem? And what was the solution? Does it make sense to get a new fuel pump anyway - after so many miles of shaking?
All the other gauges are ok.

Regards, Werner

Hi Werner, have checked on the wiring schemantics for your car and the fuel level sensor output runs on slate/green and green/black wires to ECU in engine bay on pins 19 and 20 respectively. This means there is no connection directly from sensor to gauge! It appears the sensor signal is not being received by the ECU and its responding as with empty tank, so maybe check the ECU plug. It's the larger of the two connectors. Note the sensor wires run from rear to engine loom via chassis loom so two more connectors to check. Another check (maybe try this first) on sensor itself could be made near tank after removing fuel pump/sensor connector. There should be a measurable (usually lowish) resistance across the sensor wires. If you measure an open circuit then the complete unit needs replacing.

When I disconnected my battery, to fit a tracker, I had the opposite problem after reconnecting - the gauge always showed full regardless of how much fuel I used. I ended up taking the car to a local Morgan dealer who plugged the ECU into the computer and then reset something (the fuel gauge or ECU?) and everything has been fine since.

So maybe an electrical problem that your dealer can rectify quite easily?

I had problems with the fuel gauge on my GDI and found that it gets in a twist if you disconnect the battery when the LCD display is set to something other than the odometer. I don’t know if it’s every reading or just the ones to do with MPG.


So to reset the gauge you need to:-
1, turn the ignition on and set the LCD display to the odometer.
2, turn the ignition off.
3, disconnect the battery for a few minutes.
4, reconnect the battery and all should be good.

This worked for me so I hope it will for you.
Cheers
John.