On my 1999 coupe the fuel gauge will drop rapidly from full to 1/2 tank and most of the time the low fuel light is on. After reaching 1/2 drove around for 2 days and it didn't move.
Anyone else have this issue? Possible sending unit problem?
Thank You and yes I did search
:-)

 

It's a strange one, sounds like a sensor problem to me. I'll be interested to see where this leads as I have a similar problem but in reverse. My fuel light comes on and not fill up right away, around 10-20 miles along I'll put £30 (25 litres) of fuel in but my gauge doesn't move and still shows I have x miles remaining on board computer. If I then put another 25 litres or so in my gauge leaps up to 3/4 full tank???

Sorry, not hijacking your thread but hope your problem sheds light on mine

 

Good to hear of your experience.

I've recently purchased this one and am learning it's little tricks and sorting it out.
:-)

 

Reads like the in tank level sensor is acting up. IIRC this is some kind of a float and the mechanism can be hanging up.

To check this possibility requires the fuel tank be opened up and the unit removed and examined.

 

A 4S (or Turbo) can do this. The fuel level system is a mix of mechanical and computer due to the saddle tank with two separate basins. At around half a tank the fuel level system in the tank becomes useless and the computer then takes over to calculate fuel level and range remaining based on how one is driving.

It is some fun to switch the on-board computer to miles remaining and drive in such a way, or try to drive in such a way, the miles remaining number increments instead of decrements.

Anyhow, if the tank level is real low if one doesn't add enough fuel to the tank to engage the mechanical fuel level measuring system the level can remain "unchanged" at the gage. When I fill up my Turbo's fuel tank I always fill it full. Barring the infrequent premature shut off -- which I seek to avoid by turning the gas pump nozzle almost upside down -- the fuel gage always reads full afterwards.

 

Interesting, when it reached 1/2 and remained there for a bit rather than worry I bought gas. Next time I'll let it go a little longer to see if it drops further. It was such a rapid drop to 1/2 then no noticeable change I became concerned.

Thank you for the replies.

 

I also appreciate the info and advice, thanks

 

Mine ('99 C4) stops going down somewhere around 1/2 tank on the meter. I just use the trip odometer - reset at fill-up and re-fill somewhere around 200 miles (this gives me about a 100 mile buffer should I not be able to find gas).

 

Thank you for the reply and suggestion.