Yet another fuel gauge thread

[KnifeySpoony]

I'm well aware of the poor fuel gauge accuracy/linearity with these cars. I actually thought I was a lucky one, with a decent gauge compared to others. My car is almost 4 years old and it'd been doing OK - definitely a bit non-linear. It stays at full for the first 1/4 of a tank, then started to go down pretty predictably. However, starting yesterday, it doesn't register full anymore after a fill up. I was at the track so did 5 fillups in one day. At first it only went to 3/4, then a bit less each time, now it barely shows half a tank after a fillup.

 

Any thoughts?

Edited June 2, 2025 by KnifeySpoony

[jbcollier]

Holed float?

[11Budlite]

My first thought would be something with the float too.

 

It might not be related to your issue but I figured I'd share my recent experience just in case. I was having an intermittent issue where sometimes my gauge would work and sometimes it would always read empty. I recently pulled my FP assy out and noticed that the variable resistor component had a crack in it. It's hard to see in this photo, but it's all the way through the plastic with a fine break in the electrical/resistor part. Unfortunately the sender portion is not available seperately so you have to replace the whole FP assy. I'm not sure how it happened because I don't drive it on the street with all the potholes, and I hardly ever use the curbs on track.

[KnifeySpoony]

Great pic - seems like something like that is my issue. Something causing the float to stick down. Some type of progressively increasing resistance/friction. While I look at the pump I want to see if I think the pickup can be modified to help reduce fuel starvation in left hand corners.

[Anthem]

This subject made me wonder if my scope probe is fuel safe.