1999 - fuel gauge problem

[cesarel]

MY PROBLEM...

"I have a 99 SR5 4Runner. Yesterday, I noticed the fuel gauge was reading more fuel than what was actually in there. Filled it up, gauge went to full and plunged to empty a few seconds later. Drove it about 10 miles with it reading empty and the low fuel warning flashing. I turned it off when I got to where i was going. When I turned it back on, gauge was reading full again. After driving 50 miles, it is still reading full, not moving at all. I see no fuse issues in the drivers compartment. Any suggestions for a fix to this? I appreciate any feedback from anyone who has dealt with a similar issue or may have knowledge to what it might be. I appreciate your help."

So it will be the fuel level sensor? i was reading that maybe is the whole system, that i should use an aftermarket system...

what do you think?

 

[fourwd1]

Most likely it's the fuel level gauge sending unit in the tank.
They get quirky.

 

[cesarel]

Most likely it's the fuel level gauge sending unit in the tank.
They get quirky.

thats what i was thinking, i found the sending unit at autopartswarehouse website, by a chance where else can i buy the part online?

tks. Nice Hilux!

 

[[email protected]]

I'm having the same problem with my 99 fuel gauge. After filling up the tank, the fuel gauge reads F for a few seconds, then drops to E and the low fuel light starts flashing. This typically happens as soon as I put it in gear and start moving. If the tank is not full, the needle reads F all the time.

The problems started a few weeks after having the gas tank dropped by the welder who was repairing my rusted frame. The connector looks OK and fits snugly on the tank. Gently tugging on the wires does not change the behavior.

I followed the FSM procedure to test the sender and gauge:

1) Unplug wiring harness and turn ignition on. Fuel gauge reads E and low fuel light comes on (not flashing). Seems to behave as designed.

2) Connect pins 2 and 3 on wiring harness with a 50 Ohm resistor. (FSM recommends using a 3.4W [~42 Ohm] bulb but I didn't have one handy.) Fuel gauge slowly moves upwards. Sometimes it behaves normally, sometimes the gauge drops suddenly to E after a few seconds and the low fuel light starts flashing again.

3) Measure resistance between 2 sets of connections on back of fuel gauge assembly. I have not done this step yet since it requires taking the entire dash apart and I don't have the time/desire (or a driveway to work in for that matter).

4) Measure resistance between pins on sender. Pin 2-3 = ~50 Ohm, pin 1-3 = ~150 Ohm, pin 1-2 = ~200 Ohm with approximately 3/4 of a tank.

Any ideas what the flashing low fuel light indicates? I can't find any mention of the flashing behavior in the FSM.

I've been tracking my miles with the odometer so I don't run out of gas, but I'd rather have the gauge working again. I don't want an aftermarket product like the Scan Gauge.

 

[Nates_NW4Runner]

Check the ground wire

This happened to me a couple years ago, so bear with me for the lack of specific details I can give...

Mine developed this issue after connecting an improperly wired trailer!
The first time i pressed the brake pedal, it blew the taillight fuse. Replaced the fuse several times, to no avail until I disconnected the trailer plug... All of the sudden my fuel guage would drop to empty after putting the truck in gear and the low fuel warning light would start flashing. This was NOT a fuse issue, but WAS related to my taillights... I was so confused!
I spoke with two Toyota wiring gurus who both said "the fuel guage doesn't share any wiring with the taillights so it couldn't be related"... I was stumped to say the least because this all started after the trailer incident.
One thing lead to another and i decided to dive into it myself knowing they HAD to be related. While inspecting my trailer wiring harness, I noticed the ground wire had gotten hot and the wire was somewhat melted from the inside... I added a larger guage ground wire for my taillight/trailer wiring harness and low and behold, the fuel guage now functions as it should and have had no further issues since that day.

Long story short: Check the chassis grounding point behind the left rear cargo panel (in front of your left taillight) and check for loose connections or possibly a slightly melted wire. Your issue may be farther down the chain somewhere, and could have been pulled loose from the tank/sending unit during the removal process.?.

GOOD LUCK WITH YOUR SEARCH! Feel free to P.M. me if you have specific questions.

Nate

 

[tagogi]

Exact same issue

I know this is an old thread, but I'm having the exact same problem on my 99 SR5 4Runner. I'm hoping Nates_NW4Runner is still receiving updates on this...

I noticed my trailer ground wire was frayed (pinched under the hitch). I hooked it up anyway. When we were testing lights, my wife said, "they seem really dim."

Started driving and after 10 minutes or so, the gas gauge needle dropped to the bottom of the gauge and the low fuel level light started blinking. It stays like this until I shut off the engine.

When I turn the engine back on, the gauge works for a little bit, then inevitably drops and blinks again.

Mine still happens, though, when the trailer is not hooked up. It happens faster on a warm engine, so I'm assuming the trailer light wires are warming up, increasing resistance??? and that's why it doesn't happen right away after sitting for a while.

Question for you, Nates_NW4Runner, was it occurring for you when the trailer was not attached, right? And the wire you replaced was on the 4Runner? Where does that wire ultimately lead to? and is it run inside the frame channel irons?

Thanks in advance.

 

[cesarel]

Try looking for "4runner fuel pump calibration" i did it with mine and it worked.

3rd gen fuel gauge problem: I think I figured out the problem (pics) - Page 2 - YotaTech Forums

Cheers!

I know this is an old thread, but I'm having the exact same problem on my 99 SR5 4Runner. I'm hoping Nates_NW4Runner is still receiving updates on this...

I noticed my trailer ground wire was frayed (pinched under the hitch). I hooked it up anyway. When we were testing lights, my wife said, "they seem really dim."

Started driving and after 10 minutes or so, the gas gauge needle dropped to the bottom of the gauge and the low fuel level light started blinking. It stays like this until I shut off the engine.

When I turn the engine back on, the gauge works for a little bit, then inevitably drops and blinks again.

Mine still happens, though, when the trailer is not hooked up. It happens faster on a warm engine, so I'm assuming the trailer light wires are warming up, increasing resistance??? and that's why it doesn't happen right away after sitting for a while.

Question for you, Nates_NW4Runner, was it occurring for you when the trailer was not attached, right? And the wire you replaced was on the 4Runner? Where does that wire ultimately lead to? and is it run inside the frame channel irons?

Thanks in advance.

 

[redneck4runner]

Easy fix

Mine does the same way but all I have to do is go launch it off a jump and it works for 3 months then I have to jump it again :bravo

 

[Skewedview]

Problem solved!!

1999 4Runner Limited Fuel Gauge Problem.

Vehicle is all stock, except for added trailer lights.

Problem:
After moving the car the fuel gauge drops all the way to the bottom and the yellow low fuel light starts flashing.

Peculiarities:

• With the engine on and either of two trailers hooked up the flashing light goes away and the fuel gauge works normally.
• With the engine off and trailer hooked up, when the headlights are turned on, the fuel gauge works normally with no flashing light (the gas gauge shouldn't work with the engine off and the keys out of the ignition).

What Didn't Solve The Problem:

• Replacing the trailer wiring harness.
• Cleaning and reconnecting the trailer wiring ground to the chassis.

Solution:
I also have a Mazda CX-5. The computer went nutz and showed a cascading list of unrelated problems. Sometimes the car wouldn't go when the gas pedal was pushed. I finally noticed that its brake lights didn't work when the headlights were on. Then I realized that I wasn't seeing tail lights, but full time brake lights. I finally traced the problem to a bad tail light bulb. One of the filaments was loose, intermittently touching the other causing a short, and freaking out the computer.

WTH... Could a bad bulb cause the 4Runner's problem? I thought I try pulling all of the light bulbs out of the tail lights to see if the problem corrected itself. The very first bulb that I pulled (one of the tail lights) was black inside. The bulb worked and I originally hadn't thought that anything could be wrong with any of the lights, however after examination I realized that something evil had been going on inside the bulb. As soon as I removed it the blinking low fuel light went away and the gauge worked perfectly. I replaced the bulb, calibrated the gauge as described earlier in this forum, and it has been working perfectly ever since.

Before you go dropping your gas tank or pulling your instrument cluster out, try out the bulbs first. Worked for me. Good luck.

 

[swelleriffic]

1999 4Runner Limited Fuel Gauge Problem.

Before you go dropping your gas tank or pulling your instrument cluster out, try out the bulbs first. Worked for me. Good luck.

I'll try this too for verification. I've had a '99 for just a couple of weeks and the blinking gas light. It worked fine when I test drove it but I left the lights on after and the battery drained. When I went back to the dealer to pick it up they had charged the battery but the gauge was acting up. My gauge works fine when:

• 
  It's hot as balls and the truck sits for a few hours in the sun.
  I have the front end on ramps for maintenance.
  It rains.

 

[Billy.m.herrington]

Fuel gauge is beating me down

Seems we all have similar problems but not identical which makes it confusing. Since I bought my 3rd gen a few months back it has been amazing but even during the test drive the gauge reads empty and the fuel level light flashes. I didn't think this was a big deal for the purchase price. I am assuming the sending unit is bad but I have learned that the sending unit and the fuel pump are the same assembly so replacing the one would mean replacing the other and having to drop the tank to do so. When I start my truck the fuel gauge spikes up to FULL then pauses for about 2 seconds and drops to empty and the fuel indicator light starts flashing. So I know the gauge is getting power. I know the fuel pump/sending unit assembly is working, otherwise I wouldn't be going anywhere. Before I start trying to locate an electrical issue in some random location I will try these simple tasks first. Check grounding cable behind left taillight area and check the light bulbs in the back...? This sounds silly but I have worked on old VW's before so nothing surprises me anymore. Other than what this thread recommends, does anybody else have any other ideas pertaining to my specific issue? Thanks.

 

[Billy.m.herrington]

Most likely it's the fuel level gauge sending unit in the tank.
They get quirky.

Does the fuel pump and sending unit have different electrical connectors even though they are both par of the same assembly?

 

[Billy.m.herrington]

So far I have been using rockauto, they seem to have to best pricing so far.

 

[swelleriffic]

New brake bulbs in '99 SR5 - gas gauge works now!

I did as promised a few days ago and checked the brake bulbs. Before I started, gas gauge was inop and brake lights worked fine. One bulb looked a bit corroded inside; once I put it all back together it stopped working. Replaced both with new 7443s from Autozone.

I was probably around half a tank at the time. Gauge wandered a bit at first between trips but no more of the needle drop and blinking gas light. Stabilized after 2-3 days and read normally. Just added 16.5 gallons with gauge showing 1/4 tank, needle is back above F and held there for the 10 miles I've driven since then. If something changes I'll report back, but replacing the brake lights seemed to reverse whatever gremlin popped up when the battery ran down a few weeks ago.

Weird. :noidea:

 

[Team_Jake]

I thought I solved my issue, but now I'm confused...

Alright T4R, lemme explain what's going on and maybe someone can chime in to what my problem is...

Yesterday, my gas gauge started acting up. When I started my 4Runner, it showed the correct gas level for about 20 seconds and then it would instantly drop to empty and the fuel light would flash. It did this every time I started it afterward. After reading a few different threads, it seemed like my issue was more electrical rather than the sending unit because the gas needle doesn't wander, it's either perfectly accurate or not working at all.

Seeing as the tail lights were a common culprit, I decided to check them. All the tail lights worked like normal, but after further inspecting the bulbs, one of the bulbs was black and filament between the two lead wires was kinda dangling and not really connected. Ahaa! There it is. I replaced the bulb and started it back up. Drove for about 30 seconds and the fuel level drops to empty.

I realized I forgot to re-calibrate the fuel level. After following the instructions and re-calibrating, I took it for another drive. I drove it for about 2 minutes and the fuel level is reading where I expect it to, about 3/4 of a tank. YES! I thought I might have finally solved the issue. After 2 minutes though, it instantly drops back to empty again. WTH!

A little background on my 4Runner that might give a little insight: I just installed a lift. The lift has left some rake to my 4Runner. The rear sits at about 1.5" higher than the front. I haven't gotten around to adjusting the front coilovers yet to the proper height. I drove it for 3 days after installing the lift with no gas gauge issues, and then took it in to a shop to weld on a Panhard Correction Kit (from eimkeith) yesterday. I drove it about 20 miles, parked it for 3 hours, started it and about 20 seconds later the fuel level drops. Everytime I've started it up since, it does the same thing. I checked all wires that could've been damaged when it was welded, including the trailer light wires, and nothing is out of the ordinary.

Could the rake from the lift or the weld have something to do with this? Since the burnt tail light replacement and re-calibration didn't work, I'm kinda at a loss of what it could be.

Any thoughts??

 

[SeaBass5000x]

Team_Jake, I am in the middle of dealing with an extremely similar situation as yours. My gauge issue started after plugging in an incorrectly wired trailer (which is very similar to another poster on this forum). I went through the same evolution as you, where I found some suspect tail light bulbs and replaced those to no avail. Much like the other poster I mentioned, I also discovered that when I plugged in my now correctly wired travel trailer, the gauge works correctly and accurately. When not plugged in, the gauge reads as full for few moments, then drops to absolute bottom and the fuel light blinks.

I'm not an expert on this, but after gathering every incident of fuel gauge problems on 3rd gen 4runners I could find on the internet, I felt that while a large portion of them were due to the instrumental panel "recall" and/or a faulty sending unit, a smaller subsection of them were not due to this. Of these, the only common theme I could see for those that fixed the problem was electrical ground, most typically associate with the tail lights or trailer attachment wiring. I noted that it wasn't always a broken ground connection, but in some cases insufficient ground (i.e. larger gauge wiring, or more robust connections solved the problem).

I have just begun a process of checking every ground point on my wiring diagrams starting with the closest ones to the trailer wiring and taillights. Unfortunately, some very cold weather around here stalled the process for me and I hope to continue to process when it warms a little. Please let me know if you solve yours, and I will do the same...and any other readers as well!

 

[Team_Jake]

Team_Jake, I am in the middle of dealing with an extremely similar situation as yours. My gauge issue started after plugging in an incorrectly wired trailer (which is very similar to another poster on this forum). I went through the same evolution as you, where I found some suspect tail light bulbs and replaced those to no avail. Much like the other poster I mentioned, I also discovered that when I plugged in my now correctly wired travel trailer, the gauge works correctly and accurately. When not plugged in, the gauge reads as full for few moments, then drops to absolute bottom and the fuel light blinks.

I'm not an expert on this, but after gathering every incident of fuel gauge problems on 3rd gen 4runners I could find on the internet, I felt that while a large portion of them were due to the instrumental panel "recall" and/or a faulty sending unit, a smaller subsection of them were not due to this. Of these, the only common theme I could see for those that fixed the problem was electrical ground, most typically associate with the tail lights or trailer attachment wiring. I noted that it wasn't always a broken ground connection, but in some cases insufficient ground (i.e. larger gauge wiring, or more robust connections solved the problem).

I have just begun a process of checking every ground point on my wiring diagrams starting with the closest ones to the trailer wiring and taillights. Unfortunately, some very cold weather around here stalled the process for me and I hope to continue to process when it warms a little. Please let me know if you solve yours, and I will do the same...and any other readers as well!

[MENTION=203896]SeaBass5000x[/MENTION]

I believe I solved it. Earlier, I tore apart the rear side panels near the tail lights and checked the ground wires. All looked good. I then opened up the engine bay and looked at every ground wire connection. I found a connection that looked pretty suspect. I believe the ground wire came to the front drivers side turn signal.

I had to remove 2 bolts and a nut to move the exap box out of the way. I removed the bolt connecting the ground wire to the body, cleaned everything, and put it back together.

I also pulled up the rear drivers side seat and checked the fuel pump connector. I unplugged it, cleaned it (even though it was already very clean) and plugged it back in and made sure it was snug on there.

I then re-calibrated the fuel gauge and took it for a drive. I drove 3 miles (about 8 minutes) and it read accurately the entire time, never plunging to E. I don't know if the issue was solved or not, time will tell, but this is by far the furthest I've been able to drive without it giving any issues. Before, it seemed I could only drive 100 feet before it would plunge to E.

But, time will tell, I'll report back in a couple days. If I were you I would first check all the ground connections especially with the rear lights since that is where you were having your issues. Hope you get yours figured out.

 

[Team_Jake]

Never mind, didn’t work, the fuel gauge dropped to empty 30 seconds after driving today.

Is there a way to discern whether or not it’s the sending unit? I’m at a loss otherwise.

 

[derekgroh]

There is a TSB regarding replacing a resistor in the instrument cluster, but Toyota stopped performing the repair in 2008, so you're on your own if you still have this issue. Apparently there is a resistor that is known to burn out in the dash, and once it does, the fuel gauge goes haywire.

I'm sure there are other things that could cause the issue, but I would imagine that the known issue would be a good starting point.

 

[JROTN]

fuel gauge issue

I also know this is an old post but I need help.
I just purchased a 99 SR5 and the gas gauge goes to full as soon as it is started, I can back up or just let it sit and idle and needle stays on full.
If I start going forward, most times the gauge drops instantly to empty and the fuel light flashes. Sometimes I can go a few hundred yards before it drops to E and the light flashes. If I shut it off turn the key back to on or start it the gauge instantly goes to full.
I have searched the web high and low and this is the closest post I can find to my Runners problem.
I checked tail lights and ground behind LH panel, and all is fine.

Did any of you members with this problem end up fixing yours?
Thanks JROTN