For the last few months, my Evo 8 has this problem where the gas gauge sometimes shows about 1/4 tank lower than actual. After driving about 5 minutes, it goes back up where it should be. I tried searching for this, but not getting anything useful. Maybe I don't know the right search terms here.

I do have walbro, and injectors and have run E85 before, but currently run 91,since E85 station is a little far for me. Seems like this problem started happening shortly after getting the injectors and tuned.

Freaks me out sometimes, when I start the car, and the gas light is on, and the gauge is very low. It also makes it difficult for me to switch back to E85, since I don't know the right gas reading.

I'm not sure where the gas level is. I'm assuming its on the fuel pump. Is it possible fuel is getting stuck on one fuel tank, and starts filling up the other side with the level when I'm driving around. I know the fuel return goes into one tank which should make it level out the 2 sides of the gas tank.

 

My evo 8 does the same ****. I have 146k miles. Im assuming the float aka sending unit is dieing

 

Glad I'm not the only one. I only have 85k on mine. but that could be it.

 

The fuel tank straddles the driveshaft. Each side has a separate float (fuel level sensor). The computer must average these to readings to arrive a tank level.

 

There's an ohm test for the senders described in the FSM. Testing probably requires pulling both units. Often any damage is visible.

Be careful, a friend of mine burned his house to the ground while working on the fuel tank. Maybe do the work outside.

If no problem there then maybe the cluster.

 

mine does the same thing. I just keep track of where it was when i shut the car off, and I reset the Trip when i fill up so i can keep track of how many miles i have driven. The gauge has never been very accurate for me anyway.