I've got an 01 that I recently bought with bad batteries. I replaced the 12V and the hv batteries, and all the codes cleared out. The gas gauge was flashing 1 bar and I got the message to add fuel. I first put 1 gallon in thinking at least the gauge should stop blinking. When it didn't, I added 2 more gallons. Still no change. After pulling the rear seat to look for the sending unit, we dropped the tank only to find that it's not replaceable! I don't have a tech manual or toyotatech.com subscription, only alldata. I found their test procedure and the sender seems to be working. The resistance went up and down as we tilted the tank back and forth. So I pulled the combination meter out of my wrecked parts car and the gas gauge did the exact same thing. The only thing I didn't do was to swap the gas tanks, since my helper had already put the tank back on the car. I'm still not getting any codes with techstream. I did read last night in the 2nd gen forums that the gauge will only read changes if you add over 3 gallons at one time. I drive an 01 and I always fill up when I get below 1/4 tank so I've never really added a gallon or two. Could this be all that it is? Any ideas? Do I need to find a manual or get a subscription to toyotatech.com? Thanks for any help.
When I was doing gasoline studies, I would run the tank dry and add 1 gallon of the next test gas. Then I would drive directly to the station that I'd bought the 1 gallon from. So I never really tried to 'calibrate' the flash except to measure the distance and mileage from 'flash' to dry. From memory (need to do a search in forums for "flash" and "gas" and "bwilson4web".) 1.2 gallons - NHW11 with great variability 2.1 gallons - ZVW30 with little variability Unless you have some better reason, I would recommend fill it up and then run a test: Miles and MPG to 'flash' Miles and MPG to dry (carry a 1 gallon spare gas can) I typically get just over 500 miles on a full tank and an additional 60-70 miles on flash. GOOD LUCK! Bob Wilson
All I can say is God is good. After removing, tilting, and reinstalling the gas tank, and replacing the odometer/gauge cluster all to no avail I reinstalled the original combination meter and called it a day yesterday. When I cranked the car this morning to wash it, the gas gauge showed 1/2 tank. When I took it to the gas station and filled it up, it slowly but surely came up to full. It only moved one bar at a time but it showed a full tank after about 20 or 30 seconds. I did absolutely nothing else to it.
Uhm all you need to do is fill the tank, the gas gauge will calibrate itself once full. Dropping the tank is a waste of time. You cannot change the sender unit or the fuel pump. They are both sealed inside the tank.
My Prius has had a blinking Fuel Guage (Bars Only - Constantly) for the last 3 years. It did not blink in any fashion noted in the diagnostic manual. After replacing the HV computer, I reset the connection between the HV computer and the Engine Immobilizer by turning the key to ON, without starting it, and left it for 30 minutes. This fixed the Fuel Guage, which must have been out-of-sync from the other computers. I don't know why it worked, but I'm happy it did.
