hello all,

I recently did a great repair on my 88 turbo 2, I had an inop fuel light.
This is a common prob on many cars.
The low fuel light does not come on.

What I did was first grounded the wire to check if the circuit worked, without
using the sensor/fuel sending unit in the equation.
My light came on in the warning cluster so I knew I had a bad sensor.

Having never checked the sensor out or knowing what type/principal it was,
I pulled the sending unit out and with a few ohms checks, figured out the culprit.
Its the shiny little silver can in the sending unit, and its a thermistor.
It provides continuity to ground when it is out of the flow of gasoline-wet.

The thermistors just turn to powder, disenegrate and wear away over time.
Mine was totally crumbled inside.

I checked every vendor I could find to see who still made the sensors.
Panasocnic made one similar. however they recently discontinued it.

However I found an exact replacement, and they are used on yamaha motorcycles.
They use the same sensor can, a virtually identical part.
So I bought an 8 year old one off ebay for 18 bucks.

It was a very simple repair, I just removed the old can, and soldered on the new one.
It is a one wire setup. Now my fuel light works perfectly.
I took a few pics of the process and may post them.

 

Nice find. Any particular year/model or Yamaha, or it it something they tend to reuse on everything?

 

nice. did you take pics of the steps you did ?

 

There were a few other applications where the identical silver can thermistor are used.
A few were in riding lawn mowers to intermediate tractors, and the other was yamaha motorcycles. The other bike makes did have a similar sensor, but the yamaha one looked a
little better in the pics.
The most widely used one I found was off the 1998-2003 series street bikes.
They all seemed to use the same one.
Below is a picture of the turbo sending unit and the replacement sensor I found.

 

great fix!

i came into this thread thinking it would be sweet to write a smartass comment like "did you put gas in it?" if your light was stuck on.

awesome fix but shot my joke to hell.

 

Basically I just clipped the wire on the Mazda unit directly above where it connects to the
old thermistor can, and then soldered the new can from the yamaha onto it.

I had to resolder where the can attaches to the metal arm, since they just tacked it on
with a solder blob, and that actually helps provide the conection to ground.

I also cleaned all the connections on top of the fuel sending unit with a wire brush.
It all worked like a charm.

 

yeah I put gas in it after I fixed it, ha.

A note to anyone who does this fix...
You have to solder the can to the arm, just a blob or something that will hold it,
if its not soldered on tight, the can will just wiggle and be loose on the arm, and it
wont provide the finished connection to ground.
Also be careful not to hold the soldering iron very long on the can, it could heat up
and damage the thermistor inside.

 

good find, do you know if this same issue with the fuel light also effects the fuel gauge as well? cause my low fuel light doesn't come on anymore and my fuel gauge doesn't work either lol

 

nope fuel gauge and low fuel light are two different parts

 

Yeah Brodie is right, they are different parts and seperate.
Check out the pic on here, and the wire that is spiraled...
thats what the silver sensor can attaches to, and its soldered on the upper metal arm in
the pic.
On the bottom of the arm, the metal is curved into a pocket shape, so the silver can fits
down inside it, like a finger cup, and helps hold it.
Its really a simple set up, once I got to eyeball it.

When you have the sending unit out, its a good time to clean everything too.
I also replaced the little tops screws that hold it to the tank, with stainless steel ones,
the originals looked a little rusty and new stuff is better.