Skip the auto shop - Our mechanics make house calls

Q: My new gas gauge should read from about 10 o'clock for empty and about 2 o'clock for full. My needle goes to about 5 o'clock.

asked by on

I have a 54 Chevy 3100 P/U. The original gas gauge was not working. I suspect the previous owner burned it up when they converted to 12v. I can put a volt meter on the lead wire and it reads 12v to ground. I purchased a new 12v gauge. When I installed it, the needle on the gauge swings past full and buries the needs almost 180 degrees opposite the half tank mark. If referencing a clock, the gauge should read between about 10 o'clock for empty and about 2 o'clock for full. My needle goes to about 5 o'clock, way off the scale. Nothing changes when I disconnect the sending unit. The needle does swing back when I disconnect the lead to the gauge. Do I have a bad (new) gauge, do I have a bad (miss-matched sending unit, should be 0-30 ohms unit) or could I possibly have the two wires on the gauge reversed?

My car has 100000 miles.
My car has a manual transmission.

You would need to see if the sending unit is shorted to ground. If you test it with an ohm meter you should get somewhere between the 5 and 30 ohms. If you are getting 5, then the gauge will be at full; and if you get 30, it should be at empty. If you are reading too low on ohms, then you have a shorted sender. If you’d like some help looking at this, a technician from YourMechanic can come to your car’s location to inspect your electrical system in person and let you know how to best proceed.

Was this answer helpful?

Need advice from certified mechanic? Get help now!

Over 1000 mechanics are ready to answer your question.
The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details
  • Home
  • Questions
  • My new gas gauge should read from about 10 o'clock for empty and about 2 o'clock for full. My needle goes to about 5 o'clock.

Get an instant quote for your car

Our certified mechanics come to you ・Backed by 12-month, 12,000-mile guarantee・Fair and transparent pricing

Get a quote

What others are asking

Q: Transmission fluid change necessary?

Your transmission fluid should be changed as recommended by the manufacturer. Look in your owners manual to see what mileage you should change the fluid. Most manufacturer's say about 60,000 miles for most vehicles. Some newer vehicles do not have...

Q: My hot temperature light is blinking and the temperature is below the C mark. Is it safe to drive home?

Hi there. The coolant temperature sending unit is malfunctioning and sending the vehicle the wrong information or the gauge on the dash has failed. The sending unit could have burned inside causing the computer to think that the engine is...

Q: Need advice for removing passenger side motor mount.

Hello. You may have to use a medium depth 15mm socket and a breaker bar to get them loose. In some cases you have to jack up the motor to get the angles you need since the old motor mount...

Related articles

How to Avoid Back Pain in a Car
If you have back problems, sitting in a car for an extended period of time can be excruciating. Even without back problems, you could experience discomfort and soreness from...
P2428 OBD-II Trouble Code: Exhaust Gas Temperature Too High Bank 1
P2428 code definition A P2428 trouble code signifies that the PCM has detected a problem in the exhaust gas temperature sensor circuit in bank 1, which subsequently contains the number one...
How Much Does a Mechanic Make in Vermont?
Automotive technician jobs in Vermont have an average mechanic salary of $37k, with some mechanics earning a salary of $53k.