For some reason, I enjoy getting my auto advice from this forum so I’m asking another question
For two consecutive weeks I let my gas supply in my car get low then filled it up all the way. Last week when I did it, rather than going a little past full the needle went all the way to the right like it was pinned . What I mean is rather than looking like / it looked like - As I drove around it slowly moved to the left. I put 10 dollars in today when it was halfway between l and / and it went back towards - but not all the way. I’m assuming something happened to the float in the tank that tells the guage what to register. How difficult is this to fix? I don’t want to forget I have the problem and let my car run out of gas when it still shows fuel.
At the risk of stating the obvious, either your sender (in your tank) or your gauge is cactus. My experience is that the sender is what tends to fail, but on the other hand, every time I’ve had a gauge that malfunctioned, it died (no reading) rather than going hyperactive like yours.
Assuming that your gauge is just an ordinary solid state one (and not some fancy dancy electronic gizmo) I’m a bit puzzled how the sender could give a signal that pushed your needle around too far. Usually the sender is just a variable potentiometer with a float, and when the tank is full the resistance is about nil and the voltage at about that of your battery. So how could a malfunctioning float or sender push out more voltage than the full battery voltage and send your needle beyond full?
I reckon you may have a problem with the gauge.
How hard is that to fix? Depend how accessible your gauges are. I’ve owned cars in which it was easy to acccess the back of the dash and others where it would have been less hassle to sell the car and start again! (and I’m only half joking).
This is the real problem here. If you know your mileage and how much your tank holds, you could work out where the needle is when your tank is on empty. Then get some black electrical tape, and mark your new “empty” so you won’t forget. But if the guage is hosed, this might not be reliable anyway.
Maybe they make gas cans which are safe to carry around in the trunk.
First of all, it would be more helpful if you noted how large your tank is (in gallons, dollars vs gasoline is a pretty wild variable) and how many gallons you added. I’m paying about $1.10/gal here in OKC, but I’d imagine it’s more like $1.80/gal in NYC.
That being said, Princhester’s diagnosis seems spot on. I’m having a similar problem with my Celica (the needle only travels from about 1.25 down to .5 capacity when bone dry). It started the day I removed the cluster to replace the speedo cable. The fuel guage armature was probably distorted when I accidentally dropped the cluster after removing it. Noting Princhester’s comment about what a PITA removing the cluster can be, you can see why I’ve been living with the problem for about two years now. I generally just keep track of the mileage with the trip odometer now to avoid running completely out of fuel. It helps to find out how far your car will typically go on a tank of fuel and never go more than 75% of that distance without refilling. You’ll have to get in the habit of topping off every time you stop instead of just putting in $5 or $10 when you have to, but filling up all at once instead of always running around at .25-.5 is better for the environment (fewer evaporative emmissions at the pump).
No container of fuel is safe in the trunk of a car, despite the claims on the label.
Another possibility is that the instrument cluster voltage regulator is malfunctioning. The pointer moving too high can be explained by that. You can check it by measuring the voltage it supplies to the cluster or perhaps by noting whether or not any other gauges in the cluster are behaving badly.
A Chiltons service manual (or other brand) can be helpful in determining where to measure the voltage and where the regulator is located.
Note that this is a regulator for the instrument cluster, not the better known regulator that works in conjunction with the alternator to regulate the charging voltage.
That’s not exactly true, there’s a recent trend of safe, non-volitile emergency fuels to be kept in the trunk in case one runs out of gasoline. Pennzoil Roadside Rescue is one of them, I’ve seen others.