Wanted GTA Fuel Sender Unit

Well, put it this way, even if the float is stuck at the top end of the sensor, and there is a 320 ohm resistance reading like you have, (as opposed to a short or open circuit reading), if all the rest is working, the fuel gauge will give you a reading even though it does not move. Note that that your reading of 320 ohms falls between the upper and lower limits of a working sensor, which is around 10 to 400 ohms.
I still believe substution of the " tank sender unit" is your next move.
You must get it to a stage where you have a steady reading having reset the computer after fitting the TSU, before you start thinking about dissmantling the sensor.

Jon, just going back on your problem, there is one further thought on this. Your comment that you checked the resistance with only a 1/4 tank full, I would have expected a lower reading than the 320 ohms you got. So putting my thinking cap on again, there is a possibility that the computer can detect a fault due to a stuck float and indicate it by flashing the display, which is the way Renault do it on these computer displays.... by comparing the pulses from the flow meter, ie:- usage of fuel, with the change of pulse rate from the TSU due to the lowering of the fuel level in the tank. All this depends on how they programmed the computer. So to check this is quite easy.....remove the sensor from the tank by unscrewing the clip, then turn the sensor end on end and you should be able to hear the float sliding from one end to the other. If you can hear it slide, check the resistance with it the right way up, and again when it is turned with the connector pins at the bottom. If you do this, can you post the readings here please.
John

Mines been playing silly buggers since the latest engine swap .It will not read any decrease in level but will reset to a seemingly sensible figure relative to volume when the bat is disconnected ..............
I keep meaning to look at it but instead keep peering in the tank and carry a jerry can

Lee, what year is your car, or has it got a TSU (blach box) mounted on the wheel arch?

It's '88 E.Old style I believe .No black box recorder

What I would do first is to check the part No. against those listed by Stephen above. It is imprinted on the plastic top of the sender unit. It is very important to identify your actual unit, as if it is the older style, the wires go directly to the computer from the sender as the TSU is built in, hence, I think, the higher price. I am afraid substution with another friendly Club Member`s unit would be worth exploring.
You will note that the older one is called a "Sender", and the later one is called a "Sensor", hence the TSU

Sadly the part no's have been rubbed off the top of mine, i get it out later today and see if it's still moving inside.....

[quote="jon_viola"]Sadly the part no's have been rubbed off the top of mine,quote]

If you hav`nt got the pt No. the other give away is the TSU mounted on the wheel arch.......is it there or not

Yep there although in my car mounted next to the battery on the inner wing...

Mines the old type .Cant read the numbers but the wires go straight from the unit into the dash .Had the sender out .....015 right way up ,367 upside down so it is working ,nothing sticking as I tip it .
I'll disconnect the bat and try the reset method .I'll test it out the tank ,slide it about a bit ........Put that fag out !!!!

Ok Jon, one other question, has it ever worked since the car has been yours? Let us know the readings of your unit once you have removed it from the tank. You might just also try unplugging the TSU spraying the contacts with cleaner, reconnect, reset computer, and see if anything has changed.

Lee, The readings apear to be right according to the info in the manual.

Nope never worked! Just had the sender out 8.7-64 were the readings, strange when the 1st one was 320- dodgy unit? It's def later type part nos were still readable with the unit out of the car....

Right. That has cleared up a little puzzle that has been bothering me since I said the 320 ohm reading was OK. The manual I have giving the readings for the unit, I now realise, is for the older type. Lee`s readings comfirm that, (funny these readings are still in the 1990 model year manual) BUT I have a newer type unit which I checked and found the readings to be:- the right way up 85.5 ohms, and upside down 2.6 ohms. Which now says to me that your tank sender is OK, as long as you can hear the float sliding from end to end. So the next step is to substitute the TSU.
As an exercise I dissmantled my spare one (dont make me go into how I have one) and the pics are below for your interest.





The only reason I asked if it had ever worked was I wondered, due to the 320 ohm reading you got, if a wrong sensor had been fitted by mistake by the previous owner.
Just to note your readings are slightly different to mine, but I would not worry about that to much, tolerances and all that.

John

Great thanks! I'll get on to Martin etc and see if they have one.

Well I've tested it out the tank and it seems to read when I tip it max to min .I've put it back in the tank and reset the comp .We'll see