Fuel Gauge doesn't work

[ShaggyTE]

I changed my fuel pump two weekends ago and my fuel gauge doesn't work anymore. I dropped the housing when I had it out so I figure that is the reason but the low fuel light still comes on making me wonder if it could be something else. I took it out today and checked everything over and made sure the float wasn't catching on anything and that the wires were all still good. So other than it just being broken could it be anything else?
Thanks,
Tanner

 

Check the wires again. It's easy to disconnect the sender wire accidentally.

It's ridiculously easy to get the float hung up when you put it back in.

twkd

 

[ShaggyTE]

Alright I checked all the wires again and they all had continunity. I also moved the float while I had it out with the car turned to ON to see if that would work and it didn't. The needle still sets below the E and doesn't move. So does anybody know if I can get a new sending unit from a dealer or what other cars will work?
Thanks

 

nt sure if these are linked. but my gauge will only go just a bit over the half mark. no matter how full wont get past 1/2

 

[3Diamond]

Is your fuel tank grounded well? If it isnt you may not get any reading as sender operates on (-).

 

ahh that right eh. ill have to check that out tommorow /ubbthreads/images/graemlins/laugh.gif

 

[cheekychimp]

I have changed fuel pumps a number of times and have this problem a number of times. It does seem that the fuel pump sending unit on the Mitsubishis is particularly sensitive and I have had to change the unit once as a result. That said, if you take the fuel sender out, you will notice the contact part of the switch (a small sprung clip that touches against a small plate with sort of ridges in it). Cleaning this up or very very gently bending the sprung part to achieve better contact may get a result.

Also it may sound stupid but make sure if you had the car jacked up whilst working on it that it is on the flat when you put stuff back together and test the gauge. I once dissambled and reassembled the damn thing three times before I realized it wasn't reading right coz the wheels were still jacked up ... /ubbthreads/images/graemlins/banghead.gif

Final point to consider if you have always had problems with your fuel gauge is has your gauge cluster ever been disassembled. I recently removed all 4 needles from my gauge cluster to repaint the undersides red for a sharper needle colour. Resetting the needle positions upon reassembling the unit is relatively easy for mph, rpms and temperature because you just set them for zero. However I have been told the fuel needle doesn't zero which means you have to find someway to calibrate it when reinstalling it.

 

[Hertz]

Quote:
However I have been told the fuel needle doesn't zero which means you have to find someway to calibrate it when reinstalling it.



Reinstall the cluster without the front lexan(? the clear part) and needle. Drive to gas station. Fill the tank. Put the needle back on, with it on F. /ubbthreads/images/graemlins/smile.gif When you get home, pull the cluster and put the cover back on it.

 

[Matticus]

Or do the opposite, drain the tank, and set the needle to E. Less installing/removing.

 

[cheekychimp]

Quote:
Or do the opposite, drain the tank, and set the needle to E. Less installing/removing.



Matticus,

You are 100% correct, but personally, I think Ryan's method whilst harder work is safer. Your way means that by the time you hit empty you really are empty; Ryan's method by contrast will probably leave some leeway.

Personally, I figured since I'm going to have a lot of fiddling and tuning to get done setting up the car in the first few weeks, I'll probably drive it until the idiot light comes on and then set the needle to E.

Paul.

 

[ShaggyTE]

Hey thanks for the replies guys but I can't this thing to work and I have not messed with the gauge cluster ever. So you think I can still get a new sending unit from the dealer or anybody know what other cars will work?

 

[Matticus]

Quote:

Matticus,

You are 100% correct, but personally, I think Ryan's method whilst harder work is safer. Your way means that by the time you hit empty you really are empty; Ryan's method by contrast will probably leave some leeway.

Paul.



Lol, didn't think of that. But just think how precise that gauge would be...

I personally would try anything before buying a brand new sending unit. I would pull out the unit and use a multi-meter to mack sure you have continuity though out the wiring for the gauge. Also when you take it out, double check where the wires are bolted to on the underside of the sending unit. I just did my fuel pump and had the wires swapped before I realized it. I don't know if it would have made a difference if it was but just something to check.

 

[3Diamond]

Also check for proper grounding. IIRC senders use ground to signal.

 

Additional check: just short out the gauge wire to ground. The gauge should then read F. If this works and your sender ground is good, then the sender is dead. If it doesn't the gauge or the wiring to it has a problem, which you can then trace before breaking any seals or pipe connections at the sender.
Tony

 

[cheekychimp]

Tony that's good info.

Mods: I'm not sure how/where to archive that but it sounds like a good piece of info to have on record and could save a lot of time in diagnosing a fault.

Paul.

 

[ShaggyTE]

Quote:
Additional check: just short out the gauge wire to ground. The gauge should then read F. If this works and your sender ground is good, then the sender is dead. If it doesn't the gauge or the wiring to it has a problem, which you can then trace before breaking any seals or pipe connections at the sender.
Tony



Wow thanks for that post! I checked it and the needle moved to F. Now my problem is getting a new sender /ubbthreads/images/graemlins/banghead.gif. Anybody got one they want to sell?

 

Make sure the ground to the sender is good before you replace it...

twkd

 

Yes I did say about the ground!
Glad to have helped.
By the way, you may be able to fix your existing one if you pull it out and examine it for any damage you may have done while doing that fuel pump job - worth a look?
Tony

 

[3Diamond]

I said it first! mwahahaha /ubbthreads/images/graemlins/crazy.gif

But seriously, when i helped my friend, his tank was so rusted, that i was suprised it even had contact, let alone worked!

 

Did the US market cars have a different tank? I looked inside mine recently and it was as clean and shiny as the day it left the factory in Japan ... I was expecting the worst from posts I'd read on this forum and was so relieved when I saw it.
Anyway I hope he can fix his sender - he probably just bent something when he put that fuel pump on.
Tony