Sometimes fuel disappears

[rockola1971]

You could reseat the gauge needle so it's accurate, comparing what your Tech 2 reads for fuel level % now and the gauge, then adjusting the needle. Usually when the ignition is off the needles rest a little below their zero point. When powered up with no input they'll bump up from that slightly due to the stepper motor moving from its resting point to its zero point. You could also install an accurate gauge face while its apart.

I would be curious where the zero resting spot is currently with the OP's gauge. Typically when the stepper motor starts to or totally pukes itself the needles will rest at somewhere well above Zero spot.

 

[MassHoe04]

You could reseat the gauge needle so it's accurate, comparing what your Tech 2 reads for fuel level % now and the gauge, then adjusting the needle. Usually when the ignition is off the needles rest a little below their zero point. When powered up with no input they'll bump up from that slightly due to the stepper motor moving from its resting point to its zero point. You could also install an accurate gauge face while its apart.

I have the needle alignments off a little, as I have mentioned. But, the PRNDL needs re-soldering, I'm not sure of stepper motor condition after 200k miles/18 years and a couple of cluster bulbs are out too (would like to go LED).

Must-do items take priority over the want-to items.
Such is life with an older daily driver.

Maybe after I get all the roots dug up in my yard before the landscaper comes next week, I can play with re-setting the needles to their zero points and solder the PRNDL.

In the meantime, I subtract 7 from whatever the speedometer is telling me to keep from getting speeding tickets, use the calculated miles remaining on the trip to "gauge" where I am at on fuel; and count to 3 clicks on the shift lever. Constantly doing math in my head (which sometimes hurts). It's a lot like flying a WWI airplane... By the seat of my pants! LOL

 

[rockola1971]

I have the needle alignments off a little, as I have mentioned. But, the PRNDL needs re-soldering, I'm not sure of stepper motor condition after 200k miles/18 years and a couple of cluster bulbs are out too (would like to go LED).

Must-do items take priority over the want-to items.
Such is life with an older daily driver.

Maybe after I get all the roots dug up in my yard before the landscaper comes next week, I can play with re-setting the needles to their zero points and solder the PRNDL.

In the meantime, I subtract 7 from whatever the speedometer is telling me to keep from getting speeding tickets, use the calculated miles remaining on the trip to "gauge" where I am at on fuel; and count to 3 clicks on the shift lever. Constantly doing math in my head (which sometimes hurts). It's a lot like flying a WWI airplane... By the seat of my pants! LOL

I dont think you are fully understanding what COULD BE going on here. If your stepper motor is bad then you moving the needle wont make it better. We need to know what your needle on your fuel gauge is doing when the key is turned off. More specifically where does the need rest at when key is off? This actually will give a clue as to what is going on.

 

[MassHoe04]

I dont think you are fully understanding what COULD BE going on here. If your stepper motor is bad then you moving the needle wont make it better. We need to know what your needle on your fuel gauge is doing when the key is turned off. More specifically where does the need rest at when key is off? This actually will give a clue as to what is going on.

I got ya. When the PO put the decal/plate in, I think they may have lined up needles on 0 marks, rather than marking the actual stop point of the stepper motor before pulling the needles off.

I am going to try running with that assumption. It is cheaper, easier and faster for me to go with that theory first than to assume the stepper motors are bad. Worth a shot!

Here is my cluster with key off... Looks like all the gauges line up on second index mark on the dials, except speedo is on the 4th line and Tach is on 0 (but I thought it was supposed to normally start below 0 with key off). This is why I think they simply did not index properly before pulling them off. I think they lined up on the first mark instead.

Apologies to @Rocket Man for leaving the dust on there. I know it will make you nuts.

 

[Fless]

Bingo. The needle positions can be fixed when you re-solder for the PRNDL. Then you'll have experience with dismantling the cluster when/if you need to do the stepper motors.

If you do LED backlighting, measure the bulb terminal polarity while the incandescents are still in. Or do you know that they are OE bulbs, and the PO didn't change them to LED and get them backwards? Does all the backlighting work now?

 

[rockola1971]

Ok the gauge is showing 1/16 tank at key off so you have an error of around +1/16 of a tank full. And in your first post you stated that the when trying to fill the tank the most the gauge will show is 3/4 of a full tank which would actually mean 3/4 - 1/16 of a tank full. And it appears that keeps repeating at every fill up. You also said that after filling up and taking taking turns the needle will go towards full but never all the way.

Ive seen this type of problem before and it ended being the float arm at the fuel pump module is out of its pivot physically at the fuel level sensor. Not all the way but rotated. The arm lock at the sensor might be broken off.

"About 2 months ago my fuel gauge suddenly started to stop at and around the 3/4 line with every fill up. Every few fill ups it seems that I can almost watch the needle move towards empty while driving (an exaggeration but you get the point), it really does need to be filled up again a lot sooner than normal when that happens. I don't smell a gas leak anywhere and there are no spots underneath that I can see.
Alao once in a while after filling up and taking some turns the needle will go towards full but never all the way. The needle never jumps around so couldn't be the sending unit could it? Any suggestions would be much appreciated"

 

[Fless]

Ok the gauge is showing 1/16 tank at key off so you have an error of around +1/16 of a tank full. And in your first post you stated that the when trying to fill the tank the most the gauge will show is 3/4 of a full tank which would actually mean 3/4 - 1/16 of a tank full. And it appears that keeps repeating at every fill up. You also said that after filling up and taking taking turns the needle will go towards full but never all the way.

Ive seen this type of problem before and it ended being the float arm at the fuel pump module is out of its pivot physically at the fuel level sensor. Not all the way but rotated. The arm lock at the sensor might be broken off.

"About 2 months ago my fuel gauge suddenly started to stop at and around the 3/4 line with every fill up. Every few fill ups it seems that I can almost watch the needle move towards empty while driving (an exaggeration but you get the point), it really does need to be filled up again a lot sooner than normal when that happens. I don't smell a gas leak anywhere and there are no spots underneath that I can see.
Alao once in a while after filling up and taking some turns the needle will go towards full but never all the way. The needle never jumps around so couldn't be the sending unit could it? Any suggestions would be much appreciated"

The OP never showed us his cluster. This is the problem when tacking on to an existing thread. The OP hasn't returned since the thread was started.

 

[MassHoe04]

The OP never showed us his cluster. This is the problem when tacking on to an existing thread. The OP hasn't returned since the thread was started.

Yeah... Sorry to muddle the original thread. I added my thoughts on how the miles remaining could be helpful in preliminary evaluation of whether the sending unit or the gauge is telling the truth with known full tank and how many miles the trip computer says is left before empty.

Then it kind of evolved into me saying how I use the range as my gas gauge for now, because mine seems to be off on the cluster.

Sorry for hijacking the thread!

It is kind of weird when OPs ghost. There is no sense of progress or closure with the original issue.

 

[Fless]

Yeah... Sorry to muddle the original thread. I added my thoughts on how the miles remaining could be helpful in preliminary evaluation of whether the sending unit or the gauge is telling the truth with known full tank and how many miles the trip computer says is left before empty.

Then it kind of evolved into me saying how I use the range as my gas gauge for now, because mine seems to be off on the cluster.

Sorry for hijacking the thread!

It is kind of weird when OPs ghost. There is no sense of progress or closure with the original issue.

Probably ran out of fuel and is stranded.

 

[ncalvo]

I have had my cluster repaired a couple years ago, replaced all the motors and fixed grounds etc.
I always use the trip meter to tell my range each fill up I also calculate my MPG each fillup, some fillups my gauge stops around 3/4 full or 7/8 full, sometimes it tracks to full normally.
Sometimes it stops there then slowly creeps up to full while driving. I figure its something to do with the level sensor.
I just today changed my vapor canister, purge valve, and vent valve I am curious if I notice a difference.