Erratic fuel gauge
#1
Erratic fuel gauge
My fuel guage (analog) has started to jump around erratically. It's always been rock solid... sure it would move around a touch depending on whether I was going uphill, downhill, etc. but it wouldn't be noticable.
Now, it twitches -- sometimes by as much as a 1/4 tank fluctuation. It's pretty steady when idling... mostly moves when driving. It's actually mostly accurate, though. I'm sure it's showing the correct reading when it's steady.
Funny thing is that right before this tank of gas I was running on as empty a tank as I ever have. Didn't run out of gas, but thought I was close. I filled it up and then noticed this. Probably coincidence, but who knows.
Any ideas?
Now, it twitches -- sometimes by as much as a 1/4 tank fluctuation. It's pretty steady when idling... mostly moves when driving. It's actually mostly accurate, though. I'm sure it's showing the correct reading when it's steady.
Funny thing is that right before this tank of gas I was running on as empty a tank as I ever have. Didn't run out of gas, but thought I was close. I filled it up and then noticed this. Probably coincidence, but who knows.
Any ideas?
#3
Would that be kind of a funny deal with your friends in the car. Floor the car and the fuel gauge needle goes down by a 1/4 tank. I've had friends with old muscles cars that would do that.....but they really were down a quarter tank!
S
S
#5
Try giving it a few fill ups first and see if it stabilizes too....it could be that it's just out of whack because you ran the car close to dry. If it doesn't help, then you gotta fix something.
S
S
#7
Originally Posted by maximase86
I've had friends with old muscles cars that would do that.....but they really were down a quarter tank!
S
S
Tudor that runs a 502 BBC and a 68 Camaro that runs a blown
and injected 468 BBC... both of these cars you ask, "How many
gallons to the mile do you get?"!
Scott
#8
you can also try disconnecting the sending unit wire at the fuel pump, and then driving and seeing if the problem continues, but really the only way to do that is to cut it. you can't disconnect the harness for the fuel pump because it wouldn't turn on, and the car won't run. according to the FSM for my 88 maxima, you should have these wires at the fuel pump connector:
Black is the ground.
Green/Yellow is the fuel gauge signal wire
Orange is the low fuel warning light signal wire
there will be 1 or 2 more for power.
if you haven't isolated it yet, disconnect that green/yellow wire, then turn the ignition on. the fuel gauge should drop below E. drive for a few miles, or until the problem normally starts. the gauge should stay below E still. if it's still jumpy, assume you have a short to ground somewhere between that connector and the fuel gauge. if the needle didn't move at all, assume you have a bad variable resistor in the sending unit. now with the ignition on, touch the green/yellow wire to ground. the gauge should shoot the whole way up to F.
if you'd like instructions for testing the sending unit, I can look it up.
Dan
--------------
CHEVROLET - Cheap, Hardly Efficient, Virtually Runs On Luck Each Time
Black is the ground.
Green/Yellow is the fuel gauge signal wire
Orange is the low fuel warning light signal wire
there will be 1 or 2 more for power.
if you haven't isolated it yet, disconnect that green/yellow wire, then turn the ignition on. the fuel gauge should drop below E. drive for a few miles, or until the problem normally starts. the gauge should stay below E still. if it's still jumpy, assume you have a short to ground somewhere between that connector and the fuel gauge. if the needle didn't move at all, assume you have a bad variable resistor in the sending unit. now with the ignition on, touch the green/yellow wire to ground. the gauge should shoot the whole way up to F.
if you'd like instructions for testing the sending unit, I can look it up.
Dan
--------------
CHEVROLET - Cheap, Hardly Efficient, Virtually Runs On Luck Each Time
Thread
Thread Starter
Forum
Replies
Last Post
jmlee44
4th Generation Maxima (1995-1999)
8
10-02-2022 02:13 PM
My Coffee
New Member Introductions
15
06-06-2017 02:01 PM
Forge277
1st & 2nd Generation Maxima (1981-1984 and 1985-1988)
12
06-13-2016 09:26 PM