V8 Vantage - Fuel gauge problem

[l8lue]

The fuel gauge on my 2006 4.3 Vantage has always been slow to register re-fuelling (it could take 10 mins to show "full") but I assumed this was some form of damping to prevent oscillating level indications.

Last week, with half a tank of fuel in the car, the gauge needle dropped progressively over 20 minutes to show "empty" and the fuel computer warned ---- miles.

The next time the car was started, the reading was normal. The time after that "empty". The gauge now shows only about one quarter tank when full and at random drops slowly back to "empty"

I think that there are 3 probable causes
1) Faulty sender unit in fuel tank
2) Faulty gauge
3) An electrical glitch (ie computer problem) - Note the car runs perfectly well with the fuel computer on ---- miles!

Before I attack the wrong part of the car, does anyone have any experience or knowledge of this problem?

Thanks

[l8lue]

Thanks - I'll have a look tomorrow. I have a pit in the garage so can look from underneath, or is there an easy way in from the top?

[l8lue]

Thanks for the advice. It is really helpful.

I will report back, when successful.

[l8lue]

Problem! I pulled the car out to sort the tank connections in the sunshine. However when it started, the gauge read correctly (2/3 full). Longish journey, short journeys and all is well.

As the Vantage has cured itself, I cannot investigate the fault, unless it returns. Good news for me, but I suspect it may be temporary.

I will re-post when there is something to report.