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'66: Fuel gauge not working...

  • Thread starter Thread starter bandit2
  • Start date Start date Aug 10, 2005
B

bandit2

New Member
Aug 10, 2005
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Northern Virginia
Aug 10, 2005
#1
  • Aug 10, 2005
  • #1
The fuel gauge is not working. It was working fine until the body restoration, but hasn't worked since. Any ideas how to fix?
 

krash kendall

Active Member
Nov 19, 2004
1,258
0
36
Aldergrove, B.C. Canada
Aug 10, 2005
#2
  • Aug 10, 2005
  • #2
Check the plug on the sending unit, they come off quite easily. The constant voltage unit on the back of the dash may not be functioning (the temp guage won't work either).
 
B

bandit2

New Member
Aug 10, 2005
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Northern Virginia
Aug 10, 2005
#3
  • Aug 10, 2005
  • #3
The temp gauge works.
 
F

ForceFed70

That's why they call it "dope"
Founding Member
Dec 6, 1999
4,818
1
69
BC Canada
Aug 10, 2005
#4
  • Aug 10, 2005
  • #4
Could be the wire to the sending unit or ground.

Take a digital multimeter and measure the resistance between the fuel sender/pickup plate (under the tank) and the frame. The resistance should be really low. If it's not, then the pickup isn't properly grounded.
 

dennis112

15 Year Member
May 15, 2005
1,561
36
79
Amish Wonderland of Central PA.
Aug 10, 2005
#5
  • Aug 10, 2005
  • #5
Unplug the wire from the sending unit and ground its (the wire's) conductor to the car chassis--it won't hurt anything. The gas guage should peg when grounded and be on E when it is not.

If it pegs, concentrate your efforts on the sending unit. If the guage doesn't peg, then concentrate your efforts on the guage and the wiring.
 

iskwezm

10 Year Member
May 24, 2005
4,159
20
79
Rowland Heights,California
Aug 10, 2005
#6
  • Aug 10, 2005
  • #6
mine did this too after the guage overlays,but ive been to lazy to mess with it,so i just put in 15 bucks every time i drive it
 
S

snowball

New Member
Dec 10, 2004
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Melbourne, Australia
Aug 10, 2005
#7
  • Aug 10, 2005
  • #7
iskwezm said:
mine did this too after the guage overlays,but ive been to lazy to mess with it,so i just put in 15 bucks every time i drive it
Click to expand...

I wish it would only cost me $15.00 to top up my tank.

While I don't wish to hi-jack this thread, my fuel guage is not reading correctly. When the tank is full, the guage only goes up to the 3/4 full mark. When empty, or as close to empty as I'm game to go, the guage is still reading 1/4 full. Any suggestions as to the cause?
 
6

66stangbluework

New Member
May 5, 2005
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0
Aug 10, 2005
#8
  • Aug 10, 2005
  • #8
mine does the same thing snowball
 

iskwezm

10 Year Member
May 24, 2005
4,159
20
79
Rowland Heights,California
Aug 11, 2005
#9
  • Aug 11, 2005
  • #9
snowball said:
I wish it would only cost me $15.00 to top up my tank.

While I don't wish to hi-jack this thread, my fuel guage is not reading correctly. When the tank is full, the guage only goes up to the 3/4 full mark. When empty, or as close to empty as I'm game to go, the guage is still reading 1/4 full. Any suggestions as to the cause?
Click to expand...
Who said i top it off? thats only about 5 gallons
 
S

snowball

New Member
Dec 10, 2004
44
0
0
Melbourne, Australia
Aug 11, 2005
#10
  • Aug 11, 2005
  • #10
iskwezm said:
Who said i top it off? thats only about 5 gallons
Click to expand...

That'd be great. $1.30 a litre down here. That's over $5.00 a gallon in your terms.
 
B

bandit2

New Member
Aug 10, 2005
11
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0
Northern Virginia
Aug 11, 2005
#11
  • Aug 11, 2005
  • #11
I grounded the sending unit wire and the gauge went to full. When the SUW was not grounded, the gauge remained at empty. After I reconnected the SUW to the tank, the gauge went from Empty to 1/4 full. I know the tank is about 3/4 full... so that reading is not accurate. So the problem is the sending unit?
 

tos

Founding Member
Apr 27, 2001
896
68
59
Cincinnati Ohio
Aug 12, 2005
#12
  • Aug 12, 2005
  • #12
bandit2 said:
I grounded the sending unit wire and the gauge went to full. When the SUW was not grounded, the gauge remained at empty. After I reconnected the SUW to the tank, the gauge went from Empty to 1/4 full. I know the tank is about 3/4 full... so that reading is not accurate. So the problem is the sending unit?
Click to expand...

You could be grounded but maybe not a good ground. Those sending units are just big reostats and depending on their position they send different volt readings to your gauge(Actually they are completing the ground in that circuit). A half a$$ ground will send a lower volt reading resulting in a lower level reading. So they have to be grounded to the tank good and the tank has to be grounded good and the ground strap from your engine to body has to be good etc...Ground, Ground, Its always a ground problem.
 

Kriek

New Member
Feb 12, 2004
57
0
0
Dallas, TX
Aug 15, 2005
#13
  • Aug 15, 2005
  • #13
Thank you! I was about to replace my sending unit before I read this thread. 5 minutes redoing all the grounds and the gauge is dead on accurate now. This ironically isn’t the first time a poor ground has caused me problems.

Thanks again.

- Jon
 
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