CRG Discussion Forum

Camaro Research Group Discussion => General Discussion => Topic started by: mister70s on February 12, 2020, 04:38:26 PM

Title: Fuel gauge question...and opinions
Post by: mister70s on February 12, 2020, 04:38:26 PM
Dear members,
                       I have recently purchased a 1968 Camaro and I have a question regarding the fuel gauge readings....When I purchased the car It looked to have had about a 1/4 to a 1/2 tank of gas....After registering the car I went to my local gas station and filled her up.....The gauge read considerably past full (please see attached photo)  I have not had this car long enough to run it close to empty....and it's winter time here in NY.... Is it normal for these fuel gauges to go way past F when full....and can i expect the gauge to run way past E when empty...or is there a problem with the float and rod inside the tank.....i've already run tests by unplugging the sender connection in the trunk and there is functionality in the gauge itself....I guess I'm just being paranoid because i fear running out of fuel on the side of the road...Thank you in advance....Paul D
Title: Re: Fuel gauge question...and opinions
Post by: bertfam on February 12, 2020, 06:07:27 PM
Camaro (and all other GM cars and trucks of that time period) are notorious for being inaccurate with regards to the fuel gauge reading. Most read over full when they're full so I'm not surprised as to what you're seeing. You stated that the car was approx 1/4 to 1/2 full when you filled it up, but how many gallons did it take to refill?

Ed
Title: Re: Fuel gauge question...and opinions
Post by: Stingr69 on February 12, 2020, 07:37:29 PM
I dunno....Drive around with a full spare gas can of gas or drain most of the gas and see what it reads.
Title: Re: Fuel gauge question...and opinions
Post by: 169INDY on February 12, 2020, 10:38:26 PM
The "in" Tank variable resistor is generally ranged at 0-90 (Zero to Ninety) Ohms
With
Zero = gage indication of EMPTY.
Ninety = gage indication of FULL.

as a rule additional resistance (* poor/partial ground, cruddy connectors, piched wires etc.) in the line (Circuit as a whole) or connectors can drive the needle past the full indication as these systems age.  Usually a symptom of a OPEN circuit in the fuel indication wiring is manifested as a needle driven WAY past full at all time at any fluid level, (i.e. infinite OHMS drives the gage needle fully to the right hand stop in the gage.

One trick is to fill tank, disconnect the tan wire at the connector near the trunk floor & check the resistance using Volt-Ohm Meter and test the fuel sender with tank full and see what you are getting Ohm wise at the output of the sender.

photos to follow,

JIM

Title: Re: Fuel gauge question...and opinions
Post by: mister70s on February 13, 2020, 04:19:16 AM
Ok Guys.....Thanks for the advice....I followed your lead and took it a step further...after all the tests came back good...I removed the gas from the tank...and the gauge went right to E...thank you all !!!      8)