Well, I've been having problems with both.
First the gas level died, and then the LOW FUEL light didn't work.
Amazingly, the gas level came back to normal when the LOW FUEL light went bad.

I thought I had to replace the entire fuel pump bracket assembly - over $300!
I was lucky that you could just replace just the sender (for both the LOW FUEL and gas level).
This was $90 from the Mazda dealer.
Sorry for no part number, but it wasn't on the invoice.

Job was basically remove and replace.
The sensor is secured by two nut and lock washers.
You need to remove the two nuts that secure the wires too.

I included a pic of the assembly...


-Ted

 

my buddy is having the same problem and the best part about our cars is you don't need to drop the fuel tank to service the pump... sweet

 

Does anyone happen to know what the ohm range is for the stock fuel level sending unit?

I need to use an after market fuel level gauge and I'd rather not have to buy and rig up another sending unit/ float assembly.

If I knew the output of the stock sending unit I could buy a gauge that could read that accurately and life would be a little easier.

Thanks.

 

When I first got my car, the LOW FUEL light wouldn't come on. Afew months later, I was glancing at my gauges (as every TII owner does all the time) and watched my fuel gauge go from 3/4 to way below E. I knew it couldn't have been the gauge itself, because of the way the needle moved. It moved about as fast as it does when you fill the car up and the needle is rising.

I replaced the sending unit inside the tank for ~$100 after everything. Now my fuel gauge reads correctly again, AND my LOW FUEL light works.

 

I was thinking about getting used one, but too many of them seem to be failing right about now.
It would've been a crap shoot trying to get a good one, and then how long before it fails?

I found the part number - it was on the box. :P

FB01 - 60 - 960B
"GUAGE, FUEL" - deliberate misspelled that way on the label

This should cover all 1986 - 1988 FC models, regardless of turbo or non-turbo in the *U.S.*
The US-spec 1989 - 1991 models run a bigger / deeper tank, so there should be a different part number.
I know in other countries, it's mix-n-match on the gas tank - depending if you have BLUE or YELLOW tape on the wiring harness.

I've confirmed that my fix did indeed fix the LOW FUEL light problem.
I was running quite low on fuel when I swapped out the sender, so it came on a day later.
hurray


-Ted

 

Thanks for the good info Ted. My s5 fuel gauge has been erratic lately and the low fuel light hasn't worked since I bought the car over a year ago. I'm surprised Mazdatrix doesn't sell the senders....would be a bit cheaper than dealers.

 

They don't?

86-88
http://www.mazdatrix.com/getprice.as...m=60-960B-FB01

89-91
http://www.mazdatrix.com/getprice.as...m=60-9600-FC02

 

my "low FUEL" light stopped coming on a while back. The fuel level is still ok and I try to fill up around 270 miles to avoid any issues.

 

Kool beans JPK.....I stand corrected.

 

Check the variable resistor on the unit if threads are broken then there is the problem... It is a single thread of wire wrapped around a plastic stud...

Full = 3 Ohms, Half tank = 33 Ohms, Empty = 133 Ohms, the fuel warning light is controlled by the bullet shaped sensor not the float... I have got to admit I ghetto fixed my sending unit using individual resistors one time... It worked great till I found another sending unit...

 

I took my unit out and cleaned all the contact spots were the wires go and it started working again.

 

if the sender gets flakey, or the car has been sitting for a while, those snake oil fuel system cleaners seem to do a good job of getting the sender to work again

 

on my old s4 nonturbo my problem was that the low fuel light would come on and stay on even if the car had a full tank. It tended to happen more when it was warm out... in the winter the problem went away. Yet the fuel level gauge still worked decently.

Strangely enough, I replaced the fuel pump for an unrelated reason and somehow the thing started working properly again.

 

I would really like to find someway to fix the low fuel level sensor without spending $100 because it really is not worth it especially since it will just break again. BMW uses an inductive pickup sensor for low coolant that could probally be modified to work. It is kind of bulky though.

Can somebody cut apart an old low level sensor and take some pics to show what is inside?

 

If the original one has lasted this long why wouldn't a new one last just as long? Why do you assume it'll "just break"?

 

One thing I noticed when testing the resistance of the resister with an ohm meter is digital ohm meter's won't show a little fart in the traveling sequence. So I found an old analog type ohm meter here at the shop, and you can see if the needle jumps around there is a problem at that position of travel. However, I must add that this was basically useless once I found the coil (single wire around the variable resistor) to be broken. So I THINK a visual inspection is good enough. If it looks good and still having problems check it with an analog type ohm meter if you can find one. I would like to see this part re manufactured.... thought I'd put it out there...