Celica Forums General Discussion Interior Help! Fuel gauge shows empty all the time (2000 Celica GTS)

Although, once in a blue moon it shows fully fueled, out of nowhere but gradually runs down to zero within 5 minutes of driving.

All other sensors are operational, I understand there were some 2000 models where fuel gauge and door lock systems were connected but my door locks work fine.

Here are things I have done so far:
- Replaced the entire fuel sending unit (although now it seems I didn't need replacement, because that didn't fix it)
- Checked for blown fuses in both ECU and BCU. No relevant fuses are damaged.

This is my first ever car and have no previous technical experience.

One suspscion I have (although this might be a stretch) is that, due to not having a guard liner on the passenger side of my car, a wire or two might have corroded due to mud and dust, hence affecting the fuel system. Then again, the fuel is getting pumped, and the engine seems to be receiving fuel and running just fine, the only thing that doesn't work is the fuel gauge.

Another thing I suspect might be the cause is that the hinge on my fuel door is broken and doesn't close properly. But I really don't see any connection between the fuel gauge and the fuel door.

Please provide advice, if anyone has had this problem before.

Thanks.

I'm guessing an OBDII scanner doesn't pull up any codes, does it?
Usually that problem is just a faulty fuel level switch. I think on most vehicles the fuel level switch is part of the fuel pump itself. I'm not sure if that's the case on Celicas. But it works like the float in your toilet.

If you have exposed wiring anywhere, check the sheathing, and you should probably replace any relevant fuses anyways. It's possible an old one might be faulty, but not visually obvious. cover the basis with all the cheap/free options, and work your way towards the more costly and intensive repairs. The fuel gage is digital, so there could also be another electrical issue not related to the fuel system that is causing the gage to not display properly. But that requires specialized equipment. Many shops will scan your car for free to do some basic troubleshooting before drafting an estimate for the repairs.

if you had friend with same model nearby, maybe should try swap the meter..