Fuel sender calibration

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kowality

kowality

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Just wondering, my fuel gauge is sligtly off. When my tank is full my gauge reads just under full and my tank runs on empty for a very long time.
My question, should I bend my sender up or down to make my fuel gauge read more accurately.
 
Wait ! If you plan to remove the sender you should have a new seal on hand first. Fuel costs too much to chance a leak there. MAPA online is the only source I've found for that seal.
The problem is fuel inside the float or faulty gauge anyway.
 
A few things could cause the problem your describing. check the gauge operation first using a alligator clip attached to wire from the sender attached to a good ground, the gauge should peg past the full mark. If that works the problem is with the sending unit or sending unit ground which relies on a chassis ground connection. I have seen a small metal clamp bridging the rubber fuel line out of the sender used for grounding,alsothe ring clamp around the sender touches against the tank providing a connection to ground. Sometimes that clamp is rusty or missing causing extra resistance, clean these two points of connection. Also its easy to add a extra grounding wire using a band clamp with a wire attached with a self tapping screw directly to the body. If still no sucess remove the sending unit clean in carb cleaner and make sure the brass float does not have fuel inside. The senders range is about 73 ohms empty 10 full
 
Thanks for the ideas guys, it was a new sender last year and was never calibrated. It's just sligthly off and I had the same problem when I restored my Jeep a few years back. I'm pretty sure I just need to put a little bend in it but I couldn't remember which way to go.
 
The only sender you might adjust is the fuel sender but if the arm is hitting the travel stops now, bending the arm wont make a difference at full. Senders areb't supposed to need calibrated.
Rather than crawl under the car just yet, try this.. Fill it up and check the resistance with an ohm meter. You can pierce the wire insulation in the trunk or remove the left kick panel to access the wire at the harness connector there. You're looking for 10 ohms, no less than 9.6 ohms. If you do see 10 ohms there and the gauge doesn't report full, the gauge is at fault.
If you see more than 10 ohms resistance the gauge wouldn't report full. The fault could be the ground strap at the sender, the wire connection(s) and lastly the arm not traveling to its stop.
There are threads here concerning incorrectly built aftermarket senders too. I dont think bending the float arm is the answer for that either. Good luck
 
RedFish said:
If you do see 10 ohms there and the gauge doesn't report full, the gauge is at fault.
Click to expand...

.....................or the voltage limiter is AFU

These are the resistances in the Mopar guage tester tool:

L = 73.7 Ohms (empty)
M = 23.0 Ohms (1/2)
H = 10.2 Ohms (full)

They are useful for temp, fuel, and optional oil gauge
 
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