Been trying to track down the source of a flaky fuel gauge for a week now... removed my sender today to clean and check resistance values (all but one were fine) and realized I was getting nothing on the reserve circuit. Couldn't find much in the archive so FYI to anyone without a reserve light:



That little copper tab had a hairline fracture - easily remedied with a dab of solder. Anyway, very easy to miss and worth a look if you're at wits end.

Now for the gauge. I'm trying to rule out a faulty one but everything seems to point to that. My grounds are good, both on the cluster and on the brass rivet behind the gauge itself (ran new ground and resoldered connection which ended flickering issues).

The needle experiences the full range of movement but seems to be off by just over a quarter of a tank. When I refill it goes to F, and after 100 miles it's down to half and around 300miles it's down to E.

Do these things lose calibration? Does this sound like something else I've missed?

I'd happily buy another but my understanding is that the 300d gauges are not compatible with my 240. 14pins vs 15 and different position I'm told.