Is this the fuel sender?
 

On my '87 TII (recently resurrected), the fuel gauge is acting erratic.

When I fill it up, the indicator is at the top of the scale. Fifty or so miles down the road, it drops to 1/4 tank and then slowly sinks down to below empty - same as when the ignition switch is off. It stays there until I fill up again.

Do you think this is the sender on the fuel pump assembly? It worked fine before the car was parked waiting restoration. During the fixup, I had the entire interior out, including the dash. Everything else works okay (except the Tach quit a couple of times, and started working again on it's own).

I've got a replacement I removed from an '88 N/A donor car I could substitute, but I would like some learned opinion before I disassemble the back of my TII.

Thanks for your input!


- k -

ok maybe u didnt connect somethin when u took the interrior appart
but where I would start is the sending unit since u already have one it only takes about 10 mins to change and see the difference

if u see a change good the job is done
if u dont u will have to go and trace your steps what u didnt before and find your mistake when u ripped the interior apart

Hmmm... You think it would be a disconnection even though it works when I fill the tank?

- k -

Maybe your float in your tank is filling up with gas causing it to drop and not float

But then, how does it work right when the tank is completely full?

I have the same problem. Maybe its a grounding issue? Where does the fuel level sender ground anyway?

I have had this happen a couple of times [thay were different cars thoe] when I change the sending unit this problem went away. Wat you can do is test the omes on the sending unit and if there is any brakes in it than its bad.

Dan

Another thought is the gage could be bad I had that happen to me with my 82 RX after I changed the fuel sending unit .

Dan

I broke down and pulled the fuel pump assembly - out of both cars (TII and donor car).

I put my Ohm meter on to the substitute, and found that as I move the float arm, the resistance goes from 97 ohms with the float fully down (empty) to 5.8 ohms fully up.

I did the same measurement on the one I just, moments ago, pulled from the TII, and it measured infinity, and as I raised the float arm the first reading I got was 17 ohms just before fully up to 4.5 ohms against the stop. Just the way the gauge "works" - reads empty unless completely full, then works only for the first 50 miles.

That's enough to convice me that the sender is the culprit.

I will swap senders, and post an update when I get it all back together.

Back in a few minutes.....

- k -

Okay, all done. Before, the gauge claimed I had no gas, now it registers 1/2 tank - which is just right.

So, sender it was.

- k -

glad you got if fixed

Dan