gas gauge doesnt work?

[djj624]

Anybody know how i can fix this issue, gauge worked fine till i put a new fuel pump in and now it doesnt read right. I put the fuel pump in last year but it was toward the end of the season so i decided to make fixing the issue one of my winter projects. Anyways anyone have any ideas?

Thanks

 

[unix_punk]

Whats it read? That with the tank full or empty? I of the 3 wires on the harness is for the level sender, if that wire is disconnected then you should see the gauge go way past full. Also could be that the level float got hung or stuck on something.

 

[pacecarta]

not right more? not right less ? what ???

at tank harness
center pin is sender (red wire )
black is ground
disconnect and test with an ohm meter across those terminals
what do you read at harness?
normal analog is 0 empty 90 full
if numbers relate to what you believe is in tank then the harness to the front of car of the gauge is bad

if numbers dont make sense to what you believe is in tank then the tank has to come down , pull the sender and find out why , arm contact might have gotten broken or arm might stuck over or under the sender arm stops

 

[djj624]

Sorry guys havent paid attn to it in a while due to it being winter and all. I will start her up tomorrow and check if it reads high or low, Ill get back to ya.

thanks guys.

 

[asrnj77]

Mine was reading normal (I think) and then I lowered the steering wheel, had some problems, and raised it back up. Now mine reads way over full. Did I pinch a wire? Anybody know which one?

 

[djj624]

Ok i finally got the car out and put some gas in her. Not sure how much was in there being the gauge not working and me not remembering from a couple months ago. Anyways the gauge needle was at the line in between full and half. I put 20 in her and the gauge moved to less, closer to half a tank. Went to my house for a min came back out started her up and noticed when i took off the needle went all the way past full then when i stopped it settled to its first position after i put the 20 in it. Any ideas guys?

 

[asrnj77]

For what its worth mine is doing the exact same thing. Hopefully we get an answer I'm going to try some other stuff this weekend and I'll let you know what I find

 

[pacecarta]

just dropped mine today
dash gauge read 1/2 and i knew i had less , so I pumped the tank almost dry using fuel prime wire and a hose on the fuel rail with the shrader valve removed to point where bubbles , only pumped out 4 gallons so it was lower than 1/2 tank it showed on gauge

to test tank ...disconnect tank harness at tank , on harness to tank with ohm meter.. one lead to center pin (pink) and other lead to ground pin (blk wire)
on analog cars sender should read 0ohm with arm at bottom (empty) and 90ohm with arm at top (full)

if sender had showed 10ohm (and tank is near empty ) and my dash showed 1/2 tank then the wiring to the gauge or the gauge would be next things to check not the tank .
mine tested at 50 ohms ,
obviously the problem is in tank since dash gauge reads close to what sender is showing

so I dropped tank (really easy with a lift guys )

pulled the sending unit and thought i heard the arm drop

tested the sender on the bench and it was perfect (well good enough 4ohm at bottom 100ohm at top)

reached in and found the plastic bucket (stock tank fuel reservoir) moving around a little (about an inch) and apparently jammed the sender arm, it was still fastened at the fill side of tank but moved a little at the forward side , i pushed back toward passenger side away from where the arm sits ..
thought for a moment about how i could make it stay put , in wiggling it around i felt the tab hitting the top of tank at one of the raised areas , took a hammer and dimpled in the corner of the raised humps , that fixed it .

sometimes the sender needs cleaning , sometimes the sender is broken inside , either is easy to fix if you like tinkering , i fixed one with parts from a NA hanger i had in the trash pile

 

[Underboost]

If it worked fine before then drop the tank again and make sure that nothing is hung up.

 

[Roger]

If I read your post correctly, how do you put 20 gallons of gas in an 18 gallon tank??

I'm aware of some gas stations having their pumps not reading correctly. Some stations in GA were find recently (for stealing gas).

 

[krom415]

I think he means $20.

 

[djj624]

I did mean 20 dollars. Im going to test/check everything like Pacecarta mentioned, and see what happens.

Thanks again guys