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When is the low fuel light supposed to come on in relation to the needle?
This is the first time I am this low on fuel and figured I'd pull a Kramer and check to see if my low fuel light is working properly on my '84. My fuel gauge works in the sense that it shows full when filled up and decreases from there as fuel is consumed.
As you can see from the first picture below it looks to me that the needle is just entering the low fuel light zone. The second picture is with the key in the ON position before starting. As you can see the low fuel light does work. The last picture is with the ignition OFF and you can see the needle bottomed out on the gage.
So does the needle typically get further into the low fuel light zone before the light comes on or could there be some other trigger that is not working/incorrectly calibrated?
That is what I've seen on my cars, it needs to be really really low, and I just do not trust it, also don't want to pull all that "stuff" off the bottom
My luck the light will go on and the engine will go off, LOL
It's a separate circuit from the sender float hitting the bottom that triggers the light, so it's not directly linked to the needle position and can vary between cars.
It's a separate circuit from the sender float hitting the bottom that triggers the light, so it's not directly linked to the needle position and can vary between cars.
+1 Beat me to it and phrased it much better than I would have.
That is what I've seen on my cars, it needs to be really really low, and I just do not trust it, also don't want to pull all that "stuff" off the bottom
My luck the light will go on and the engine will go off, LOL
Dave
Thanks. Good to know. I had the tank out last summer and completely cleaned it and replaced the fuel strainer. I am probably about 70 gallons of fuel total since the refresh, so hopefully no "stuff" has formed yet.
Originally Posted by SeanR
All the ones I've tested out to the light going off, I fill up and there was roughly 4 gallons of gas left.
Thanks Sean. Yeah the owner's manual states that the light will come on with "about 2.11 US gallons left". Will be interesting to see how much fuel it actually takes.
Originally Posted by gazfish
It's a separate circuit from the sender float hitting the bottom that triggers the light, so it's not directly linked to the needle position and can vary between cars.
Great info. Thanks. I replaced the fuel sender with a "working" used unit when I did the fuel tank refresh. I didn't think to test this when I had it plugged in but still out of the car. I did run the float up and down and verified the needle was moving, but I don't remember if the light came on or not when it reached the bottom.
Well, first off, the "gunk on the bottom of the tank" is a myth.
Where do you think the pickup is?
Don't you think that the bouncing and shaking while driving down a bumpy road would mix up what's in the tank?
Also:
As Sean noted, the CWL (! light) comes on when the low fuel light comes on, just as it does with any warning light on the cluster. Scared the crap outta me the first time.
I replaced the fuel sender with a "working" used unit when I did the fuel tank refresh. I didn't think to test this when I had it plugged in but still out of the car. I did run the float up and down and verified the needle was moving, but I don't remember if the light came on or not when it reached the bottom.
Hopefully the replacement wasn't from an S4 or newer as they only have 2 pins instead of 3 and your light will never go on !
On my '89 digi-dash car, the light comes on when the needle indicates about 1/8 remaining. The warning that comes up is "Check Range!", which typically displays about 50 miles remaining when the light comes on.
That said, I seldom if ever allow the tank level to drop below 1/4 indicated. The fuel pumps, particularly the in-tank pump, actively rely on fuel for lubrication and cooling. They just don't like to be run dry, and seem to fail at a much greater rate after a few run-dry episodes.
Well, first off, the "gunk on the bottom of the tank" is a myth.
Where do you think the pickup is?
Don't you think that the bouncing and shaking while driving down a bumpy road would mix up what's in the tank?
Also:
As Sean noted, the CWL (! light) comes on when the low fuel light comes on, just as it does with any warning light on the cluster. Scared the crap outta me the first time.
Mine comes on with approx 5 gal in the tank.
++1....try driving down a state highway (not interstate) with no moon...about 3am and the entire inside of the car turn into red lightning...I literally yelped and within 1/10000th of a second scanned every single thing in the dash to make sure I wasn't losing a timing belt!
My low fuel light never came on, no matter how low the fuel level got, except during bulb check like yours (since I've owned it anyway). My 'fix' was to clean and improve contact at the fuel-level sender connector. If you've already cleaned the connector during replacement, try pulling it apart again and bend the female contacts together a little more. Worked for me! My light now comes on around the second tick mark.
Well the light came on just as I pulled into my driveway after work yesterday. So cool, it works. Filled it up just now and it took 18.6 gallons. So like Sean has experienced it had about 4 gallons left. Conservatively I will budget for 40 miles after the light comes on before I need to get gas. This will leave at least more than a gallon left by the time I get to a pump. Unless I am being chased by Libyan terrorists at WOT, in which case I better make it 20.
08-22-2017, 03:42 PM
When is the low fuel light supposed to come on in relation to the needle?
