gas gauge

[Metclub]

So I replaced the fuel pump in my car now the gas gauge only reads a little over a half a tank. I know this is incorrect because I just filled the tank. Any suggestions?

[AleroB888]

So I replaced the fuel pump in my car now the gas gauge only reads a little over a half a tank. I know this is incorrect because I just filled the tank. Any suggestions?

Measure the resistance across the sender leads. I believe that should give you a reading of about 220-250 ohms when tank is full (I am estimating from one I have off the car).

[Metclub]

Will do thanks for the advice

[juanvan]

10-2-1 bad ground
Dropping the tank when full, usually a bad idea - can you get to it with out dropping it?

[Mike Jung]

It could be something when you changed the fuel pump.

or
Fuel level sending unit.

Have a read: Fuel Level Sensor (http://www.grandamgt.com/forum/showthread.php?t=14550)

Note: You don't have to replace the whole thing.
They have a "kit" now to fix the the part of it that needs changing.
Because it will comeback with time, as the silver used in the units will be effected/react with the fuel used; & stop working again later in it's life.

ie: sulphur corrodes it.
But the good news is (here at least) they are making lower levels of sulphur in today's gasoline.

1st try a total fuel system cleaner in the gasoline tank.

Try using a total 'premium fuel system treatment/cleaner', like: Chevron TECHRONŽ Concentrate Fuel System Cleaner or Castrol Syntec Power System Premium (synthetic) Fuel System Treatment that cleans out the entire fuel system, not just the injectors.

& try using a different brand of gasoline (maybe it will have less impurities & less sulphur).


PS: When you change the fuel pump: Does it come with a new fuel level sending unit ?

[Metclub]

Well the odd thing is once it gets to a half a tank of gas the gauge actually reads correctly. I bought a used fuel pump because $200 was a little steep right now. When I dropped the tank there where 2 plugs 1 off the pump 1 going into the car I believe. I unplugged both plugs is there a chance I may have put them in backwards?

[juanvan]

They should not be the same connectors, But I have never seen them before.