My fuel gauge randomly goes up and down while I'm driving. This has been happening for a while, but I can't find any forum threads or posts of people talking about it. Does this happen to anyone else, or is it just me?


These were taken roughly 20 minutes apart

 

My 1997 does this every once in a while with a swing of about an eighth of a tank, usually around the 1/4 full mark. I'm thinking it's a sticky float but it hasn't bothered me enough to do anything about.

 

I've had it happen once on my 98 convertible. After filling up, the gauge wouldn't move off empty. I left it for a few days and all was right. Those sender units have probably been in there for 20 or more years. We all get weary with age!

 

As your fuel gauge fluctuates, does your Range display on the speedometer also fluctuate (select range by pressing on the end of the indicator stalk)? This will answer whether it's the gauge or the sender.

 

mine confirms to this determination. ie both the fuel gauge and the “range to empty” are always matching in error.

One interesting thing I’ve discovered during every long distance trip I’ve taken with the 2002 XKR: when given a few hours on the road, the old float mechanism decides to act right and gives totally correct information for the rest of the trip.

I think it’s the constant vibration that finally frees up the sticky float and allows it to move up and down as it was designed to do.

For me, it’s just one of those endearing idiosyncrasies that make the car unique. And I have no intention of fixing it unless I have to dig into the fuel tank for other reasons.

Z