Fuel Gauge issue - Desperate
#1
Fuel Gauge issue - Desperate
Good evening everyone, I'm new to the forums but I have checked plenty of post here. Anyway I know that there have been plenty of posts already for this issue but unfortunately none of them has seem to solve my issue or the post has never been continued.
My fuel gauge has been inaccurate for over a year now, I'm a little mechanically inclined so I decided to do some research(checked almost every single post about inaccurate gauge), so I've replaced instrument cluster and both fuel sending units(and the fuel pump have been replaced about 2 years ago as well). The gas gauge only goes a little above half when full tank(only reason why I know is I open the tank so check both sending units again and it overflowed...)
would definitely appreciate any input or if anyone has resolved the same issue I'm having.
My fuel gauge has been inaccurate for over a year now, I'm a little mechanically inclined so I decided to do some research(checked almost every single post about inaccurate gauge), so I've replaced instrument cluster and both fuel sending units(and the fuel pump have been replaced about 2 years ago as well). The gas gauge only goes a little above half when full tank(only reason why I know is I open the tank so check both sending units again and it overflowed...)
would definitely appreciate any input or if anyone has resolved the same issue I'm having.
#3
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Front and rear cameras, tire pressure for all four tires can display on screen,folding side view mir
Good evening everyone, I'm new to the forums but I have checked plenty of post here. Anyway I know that there have been plenty of posts already for this issue but unfortunately none of them has seem to solve my issue or the post has never been continued.
My fuel gauge has been inaccurate for over a year now, I'm a little mechanically inclined so I decided to do some research(checked almost every single post about inaccurate gauge), so I've replaced instrument cluster and both fuel sending units(and the fuel pump have been replaced about 2 years ago as well). The gas gauge only goes a little above half when full tank(only reason why I know is I open the tank so check both sending units again and it overflowed...)
would definitely appreciate any input or if anyone has resolved the same issue I'm having.
My fuel gauge has been inaccurate for over a year now, I'm a little mechanically inclined so I decided to do some research(checked almost every single post about inaccurate gauge), so I've replaced instrument cluster and both fuel sending units(and the fuel pump have been replaced about 2 years ago as well). The gas gauge only goes a little above half when full tank(only reason why I know is I open the tank so check both sending units again and it overflowed...)
would definitely appreciate any input or if anyone has resolved the same issue I'm having.
http://www.nicoclub.com/service-manu.../Sedan/2008/FL
See page FL-5
Did you follow those instructions?
Did you use OEM parts?
Telcoman
#4
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Yep, unplug the fuel pump and use a digital multimeter to read resistance (ohms) across the pins mentioned in the FSM. 3-40ohms on one and 3-80 on the other depending on how much fuel is in the tank. Since you are having problems with not reading above 50% fuel I would test both of those with a FULL tank...
If the electrical reading checks out then you either have faulty wiring to the combination meter (you can unplug the harness on the back of it and read resistance again, steps are in the FSM, OR you STILL have a faulty combination meter. It's possible you bought a used one that was faulty to begin with.
If the electrical reading checks out then you either have faulty wiring to the combination meter (you can unplug the harness on the back of it and read resistance again, steps are in the FSM, OR you STILL have a faulty combination meter. It's possible you bought a used one that was faulty to begin with.
#5
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Front and rear cameras, tire pressure for all four tires can display on screen,folding side view mir
Yep, unplug the fuel pump and use a digital multimeter to read resistance (ohms) across the pins mentioned in the FSM. 3-40ohms on one and 3-80 on the other depending on how much fuel is in the tank. Since you are having problems with not reading above 50% fuel I would test both of those with a FULL tank...
If the electrical reading checks out then you either have faulty wiring to the combination meter (you can unplug the harness on the back of it and read resistance again, steps are in the FSM, OR you STILL have a faulty combination meter. It's possible you bought a used one that was faulty to begin with.
If the electrical reading checks out then you either have faulty wiring to the combination meter (you can unplug the harness on the back of it and read resistance again, steps are in the FSM, OR you STILL have a faulty combination meter. It's possible you bought a used one that was faulty to begin with.
What he said!
If you still have the previous combination meter try putting that one back in.
Never a good idea to just throw used parts without confirming exactly what part is actually defective.
Telcoman
#6
Have you followed the troubleshooting steps in the FSM prior to just throwing parts?
http://www.nicoclub.com/service-manu.../Sedan/2008/FL
See page FL-5
Did you follow those instructions?
Did you use OEM parts?
Telcoman
http://www.nicoclub.com/service-manu.../Sedan/2008/FL
See page FL-5
Did you follow those instructions?
Did you use OEM parts?
Telcoman
#7
Yep, unplug the fuel pump and use a digital multimeter to read resistance (ohms) across the pins mentioned in the FSM. 3-40ohms on one and 3-80 on the other depending on how much fuel is in the tank. Since you are having problems with not reading above 50% fuel I would test both of those with a FULL tank...
If the electrical reading checks out then you either have faulty wiring to the combination meter (you can unplug the harness on the back of it and read resistance again, steps are in the FSM, OR you STILL have a faulty combination meter. It's possible you bought a used one that was faulty to begin with.
If the electrical reading checks out then you either have faulty wiring to the combination meter (you can unplug the harness on the back of it and read resistance again, steps are in the FSM, OR you STILL have a faulty combination meter. It's possible you bought a used one that was faulty to begin with.
would definitely try that, only reason why I replaced it is because I have no clue on what I'm doing(I'm being honest) so I put all the post I've read and replaced what other folks have done which now I understand I shouldn't have. Thanks. I'll post my findings later. At this point I've replaced everything that would affect the gauge so the only haven't done is checked the wires.
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#8
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It's pretty simple and the FSM has good pictures of exactly where the pins are at in the harness, all you need to do is set your digital multimeter to OHMS and put the probes on the correct pin. The meter will give you a reading measuring the resistance (measured in ohms), set the meter range to something like 100ohms, not 1K, 10K, etc. You don't want to be measuring THOUSANDS (K) of ohms.
A full tank should read 3 ohms, an empty tank should read 80 when measured at the connector at the top of the pump assembly which is accessible without removing the pump.
Section GI in the factory service manual has the steps on about page 19 or so, it's under "combination meter fuel level sensor unit".
A full tank should read 3 ohms, an empty tank should read 80 when measured at the connector at the top of the pump assembly which is accessible without removing the pump.
Section GI in the factory service manual has the steps on about page 19 or so, it's under "combination meter fuel level sensor unit".
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Look here for the appropriate type of car and year. https://g35driver.com/forums/faq-diy...e-manuals.html
#12
Hey cleric670 (and everyone),
I have the same issue with my fuel gauge, and after replacing both sides of the tank (fuel pump/sender and sender), I still have the issue where when I fill up it points to the sky and gives me an SES light, once I drive 100 or so miles, it goes into the normal range and won't throw a code. Cleric, if the range is 3-40 and 3-80 respectively, where the lower end of the ohms is a full tank, could I simply install an in-line 0-100 ohm potentiometer and add the necessary resistance to keep the needle at/below the F in order not to throw a code? Knowing I have a bigger issue in the future, I can get 2 potentiometers for $10 on amazon and it's a 30-minute snip 'n solder job. Then I would have control over how much resistance passes through and can get a new SOTP of the fuel gauge range. I know it's redneck but it sounds kind of fun and the skill and tear-down level required is low. Maybe as little as 3-5Ω could do the trick and oooo... it's adjustable. The girls love that, right? ha
Thoughts?
I have the same issue with my fuel gauge, and after replacing both sides of the tank (fuel pump/sender and sender), I still have the issue where when I fill up it points to the sky and gives me an SES light, once I drive 100 or so miles, it goes into the normal range and won't throw a code. Cleric, if the range is 3-40 and 3-80 respectively, where the lower end of the ohms is a full tank, could I simply install an in-line 0-100 ohm potentiometer and add the necessary resistance to keep the needle at/below the F in order not to throw a code? Knowing I have a bigger issue in the future, I can get 2 potentiometers for $10 on amazon and it's a 30-minute snip 'n solder job. Then I would have control over how much resistance passes through and can get a new SOTP of the fuel gauge range. I know it's redneck but it sounds kind of fun and the skill and tear-down level required is low. Maybe as little as 3-5Ω could do the trick and oooo... it's adjustable. The girls love that, right? ha
Thoughts?
#13
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Front and rear cameras, tire pressure for all four tires can display on screen,folding side view mir
A fuel gauge is not really needed if you have a functioning odometer. Many early vehicles did not have a fuel gauge.
Fill your tank, set odometer A to zero and drive 200 miles. Record the number of gallons to fill up and calculate your MPG
Repeat and drive 250 miles and obtain the resulting MPG
After repeating 5 or 6 times you'll know when its time to visit your local station
Problem solved!
Fill your tank, set odometer A to zero and drive 200 miles. Record the number of gallons to fill up and calculate your MPG
Repeat and drive 250 miles and obtain the resulting MPG
After repeating 5 or 6 times you'll know when its time to visit your local station
Problem solved!
#14
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