Fuel gauge testing - The 1947 - Present Chevrolet & GMC Truck Message Board Network

Purs · 03-09-2003, 10:25 AM

How do I test to see if my fuel gauge is working or if my sending unit is messed up. Right now my gauge reads WAY past full. If I unplug the tan wire from the fuse block or the sending unit the gauge doesn't move. I used to know how to do this but now have forgotten.... old age I guess.

Purs · 03-09-2003, 11:21 AM

thanks anyway, I figured it out.

short step · 03-09-2003, 09:12 PM

how did you do it i have the same problem, and what caused it

JimKshortstep4x4 · 03-10-2003, 08:43 AM

A quick way to check out your gas gauge is to disconnect the wire on the tank unit. Gounding the wire should make the gauge go to empty. Disconnected should make the gauge go past full. If that works that way, you have tested your dash gauge, your wire, and if you grounded the wire to the tank, you have checked the tank ground.

If your readings are bad, then the problem is probably in your sending unit. To test the unit, remove and check with an ohm meter. the ohm readings should be "0" at the empty position of the float and 90 at the full position. You should get a linear reading from 0 to 90 ohms as you move the float from empty to full.

Jim

68LSS1 · 03-10-2003, 12:56 PM

Nicely put JimKshortstep4x4. You can also bend the rod that holds the float to tweak it a little.

gman · 03-10-2003, 04:03 PM

Jim,

Thanks for the tip. How's the temps in Michigan. Brrrrrrrrrrrr

I'm originally from Battle Creek but don't let that get around.

I actually miss Michigan sometimes. The salmon and steelhead fishing and the fall colors. But the mountains out here make up for it.

03-09-2003, 10:25 AM	#1
Purs Got Big Block? Join Date: Apr 2000 Location: West Texas Posts: 1,510	Fuel gauge testing How do I test to see if my fuel gauge is working or if my sending unit is messed up. Right now my gauge reads WAY past full. If I unplug the tan wire from the fuse block or the sending unit the gauge doesn't move. I used to know how to do this but now have forgotten.... old age I guess. __________________ "Experience is what you get when you didn't get what you wanted."

03-09-2003, 11:21 AM	#2
Purs Got Big Block? Join Date: Apr 2000 Location: West Texas Posts: 1,510	thanks anyway, I figured it out. __________________ "Experience is what you get when you didn't get what you wanted."

03-10-2003, 12:56 PM	#5
68LSS1 Registered User Join Date: Dec 2002 Location: Tampa Posts: 1,191	Nicely put JimKshortstep4x4. You can also bend the rod that holds the float to tweak it a little. __________________ '68 Short Step LS1/T56, Hydratech, Fatman Fabrications Stage III, Baer, Hot Rods to Hell, US Body, S&W, etc

03-10-2003, 04:03 PM	#6
gman Registered User Join Date: Nov 2000 Location: Ogden, Utah Posts: 290	Jim, Thanks for the tip. How's the temps in Michigan. Brrrrrrrrrrrr I'm originally from Battle Creek but don't let that get around. I actually miss Michigan sometimes. The salmon and steelhead fishing and the fall colors. But the mountains out here make up for it. __________________ 72 Chevy SWB Custom Deluxe K10, 350/SM465, PS, PB, Fact. Air 2000 Harley...Wide Glide

03-09-2003, 09:12 PM	#3
short step Registered User Join Date: Dec 2002 Location: Ludlow,MA Posts: 145	how did you do it i have the same problem, and what caused it

03-10-2003, 08:43 AM	#4
JimKshortstep4x4 Senior Member Join Date: Jul 2001 Location: Muskegon,MI,USA Posts: 6,026	A quick way to check out your gas gauge is to disconnect the wire on the tank unit. Gounding the wire should make the gauge go to empty. Disconnected should make the gauge go past full. If that works that way, you have tested your dash gauge, your wire, and if you grounded the wire to the tank, you have checked the tank ground. If your readings are bad, then the problem is probably in your sending unit. To test the unit, remove and check with an ohm meter. the ohm readings should be "0" at the empty position of the float and 90 at the full position. You should get a linear reading from 0 to 90 ohms as you move the float from empty to full. Jim



Register or Log In To remove these advertisements.

Register or Log In To remove these advertisements.