3rd gen gas gauge issue

[diverscale]

Having gone well over a month and 5-6 fuel tanks, with a fuel gauge that acts perfectly normal, I can now say with confidence that the ground wire fix corrected my problem.

I am glad that I can now trust my gauge instead of my watching my odometer, to know when to re-fuel.

I am extremely glad that I did not drop my fuel tank and replace an expensive part that was actually working just fine. I would have been extremely pissed had I done that, and the problem persisted.

If your gauge flakes out on you even just occasionally, do yourself a favor and invest maybe $5 and a half hour of your time, and there is a good chance that your problem will go away. If it doesn't, then you didn't lose much at all.

Always try the easiest and simplest things first!

On a related note, I have learned that things are very often not what they seem. For years, I just knew that I had a defective fuel sending unit, and being a lazy tightwad, I just sucked it up and lived with the problem (while running out of gas several times).

Another time, based on symptoms, and my questions answered here, I just knew that I had a blown head gasket. I did one final test and determined that I didn't have one, and then found that I had a faulty fuel injector instead. Imagine how extremely pissed I would have been, had I paid $1,500 - $2,500 to have the head gaskets replaced (with the necessary related work), or replaced them myself, and the symptoms still persisted.

what were the symptoms of the bad injector, and how did you know it was the problem? Those are sometimes tricky to diagnose

Also, I think, even though the 4runner does not have a fuel gauge problem, I will do the ground splice on that fuel sending unit, just to be sure.

 

[FD7683]

My splice job fixed the issue I had and my gauge has been working fine ever since.

 

[heatmyzer9]

I would love to get that kind of mileage. I have to fill up by 240 miles or it runs dry.

My gauge has been in full retard mode the past month or so, dropping to E and flashing when it feels like it. I had it in for inspection two years ago and the mechanic said it was the gauge when I asked about it. At that time it was just reading Full to Half. He offered to fix it but I declined and just followed the miles.

I have a 99, SR-5 and had the same thing happen twice. Startup, gauge on full, wait couple of seconds, gauge crashes to below empty, gas warning light starts to blink. Argggh.
I saw an old post that showed a burned out component on a board on their cluster that was blinking the gas light. The component is on the board behind the small white cover on the back of the cluster. Just unscrew the screws, take of the cover, unscrew the small circuit board and disconnect the ribbons and one small wiring connector on that small board. Behind the small board (on the main board) is an inductor labeled “L9”. Since it literally failed and smoked for the guy in the old post…..I decided to check continuity across that component. It had no continuity and had failed (no physical signs of failure though). One side of L9 leads directly to a pin on one of the cluster’s connectors. So I soldered in a 1 ohm resistor (didn’t have any inductors) bridging out the bad “L9” inductor. It worked fine after that.
I think that component pulls higher current when the resistance of the gas float drops/or the sender goes bad. I changed out a fuel pump and it even smoked the new resistors…did the repair again and no issues. For some reason when the gauge starts acting up, that component fails due to high current.

 

[Outrider]

what were the symptoms of the bad injector, and how did you know it was the problem? Those are sometimes tricky to diagnose

Also, I think, even though the 4runner does not have a fuel gauge problem, I will do the ground splice on that fuel sending unit, just to be sure.

disclaimer: I didn't mean to derail this thread, and only mentioned the injector to illustrate my point about things often not being what they seem.

The symptoms were a rough idle and a misfire code in one cylinder. There were also several other symptoms that led me to believe it was a leaking head gasket. (it was a very long and complicated train of thought) What nailed it down to being a faulty injector was when I swapped a coil pack between cylinders, and the misfire remained in that cylinder. Then I replaced that one injector with a $40 rebuilt one, and the problem disappeared. After that, I did the job correctly and replaced all of the injectors.

That was about 5 years ago, so the details I recall are fuzzy. I hope my explanation makes sense.

 

[Danger Mouse]

when I got my 2000 the fuel gauge didn't work. found a reset procedure on here somewhere, maybe it was a different 4runner site, not sure. after the reset mine has worked without issue for the past year.

 

[diverscale]

disclaimer: I didn't mean to derail this thread, and only mentioned the injector to illustrate my point about things often not being what they seem.

The symptoms were a rough idle and a misfire code in one cylinder. There were also several other symptoms that led me to believe it was a leaking head gasket. (it was a very long and complicated train of thought) What nailed it down to being a faulty injector was when I swapped a coil pack between cylinders, and the misfire remained in that cylinder. Then I replaced that one injector with a $40 rebuilt one, and the problem disappeared. After that, I did the job correctly and replaced all of the injectors.

That was about 5 years ago, so the details I recall are fuzzy. I hope my explanation makes sense.

Thanks for the details. Will remember that as I never (and hopefully never) encountered this problem.

 

[LivingHI]

My 99 would always drop to e shortly before start up. The fix for me was plugging in fog lights that was missing when I bought it. Been working good after that

 

[PiperPA44]

Fuel Gauge Won't Work After Tank Fell HELP

I have a 2002 SR5 4x4

Last year I accidentally dropped my fuel tank while replacing the skid plate. It tore the sending unit / fuel pump wires out. I had it fixed by a shop but since then my fuel gauge has never worked. It powers on but only ever shows just above empty with the low fuel light on.

Yesterday I replaced the sending unit with a new one. No change...

I also tried swapping the wire orientation on the fuel pump / sending unit plug around in case the shop did it wrong. Still nothing..

When it dropped originally, the whole dash cluster acted weird like a fuse was blown.

I tried swapping the fuse for the gauges Still nothing.

I also spliced into the black and brown ground wire and attempted to ground it on a section of bare metal on the body I sanded and on various bolts. It didn't work..

Am I missing something? Can someone help?

*New user sorry if I'm posting in the wrong forum.

 

[KorbinB]

Probs just need a new harness and maybe a fuel pump. Might be able to swap harness from inside below the back seats