95carrera

My low fuel light never comes on. I know bulb is working because when you turn key it comes on. When I bought car last year gauge was not working, turned out to be typical wear to ribbon electric thing. That was repaired. Reading at low fuel is sketchy so I watch trip odometer when I get close to 250 I get gas. Any ideas? Would like reserve light yo function correctly.

gazfish

What year, older cars have a third connection on the level sensor and grounding it should put the light on. I think later cars with a digital dash work on just the level to trigger the light.

Wisconsin Joe

If you are only running it 250 miles, you aren't getting it low enough.

How much is the most fuel you've put in when it was "low"?

And I know what you mean about "sketchy" fuel gauge. Mine reads below 1/4 fairly soon, but will only take 15 or 16 gals when it's down almost to the empty line. And keep in mind that the bottom part of the gauge is pretty tight. From full to 3/4 is almost as far as from 3/4 to E.

I didn't think mine worked either. Until it did. Was way low on fuel when it came on (! light comes on too). Drove another 30 miles and put in less than 20 gals (nominal cap is 23).

SeanR

When the light comes on you will have approx 4 gallons of fuel left and it will take close to 18 gallons to fill. How much are you putting in at 250 miles?

95carrera

i ran it out of gas testing light. Coasted into station I think there was about 260 on it at the Time.

SeanR

How many gallons of gas did you put in? That was the important question. If you are only getting 260 miles out of a tank, your car is not running properly.

There is a way to test the sender, here are a couple of links.

https://rennlist.com/forums/928-foru...nt-w-pics.html

https://rennlist.com/forums/928-foru...-question.html

https://rennlist.com/forums/928-foru...ge-wiring.html

Hope those help.

95carrera

Gauge is working mostly. I drive it pretty hard. It does have Porken chips. I need to try getting it down to bottom again. I have put 20 or more gallons in with out light coming on.

So here is the real question: exactly what triggers the light? The needle location on gauge? If so that connection may be bad.

SeanR

Ok, that tells me you are able to fill the tank up properly. The light should trigger around the 4 gallon left in the tank and the light is triggered by the float in the sender when it gets to a certain point. You may either have a broken wire in the connector, bad sender or some wire busted along the loom to the gauges. The fact that your gauge light works with the key on unstarted tells me that it's at the back of the car.

You can pull the sensor out (after you've run the tank down) and take it apart and you might possibly be able to fix the issue. Sadly they are no longer available new from Porsche. Not yet anyway.

95carrera

Thanks. When I bought car last June it did not read at all. I pulled sending unit, cleaned it up and nothing. When you say sensor, are you referring to something other than the cylinder sending unit? I took it to shop and they pulled the pod and I think sent it off somewhere to repair ribbon? Not sure really.

SeanR

Yep, the sender in the tank. Top of the tank.

95carrera

So I need to check this yellow wire apparently?

95carrera

244 miles
Filled the tank with 19 gallons so I had two gallons to go (approx)
Acc position to light dash, full tank. That's as high as needle goes.
Is this consistent with other S3 experiences?

The Forgotten On

Needle is working better than most. A lot of them read 1/4 tank low.