2000 trailblazer 153k miles fuel gauge has been working fine then on day i stop to get gas go to leave and its going from to half to full back and forth wait a few mins doesnt stop leave go home still doing it but when i put it in gear it stops soon as i put it in park or nut its bouncy all over again any ideas? thanks

 

My '95 used to do that. I never fixed it but I assumed it was either a short for the gauge or the float was busted. It wouldnt happen all the time though, it only happened randomly.

 

yeah im wondering if it is the float/sending unit i filled it and was fine for a day or two

 

This has always happened to my friends blazers about a year out from their fuel pump dying on them. Mine is doing the same thing right now and I have the new fuel pump sitting about 5 feet from me waiting to be put in this weekend.

 

yup its the sending unit mine did this and i dropped the tank cleaned up all the contacts and re assembled hasn't done it sense

 

I am experiencing a similar issue,a little unerving to head home from work at 2am and the tank show dead empty,but its also kind of nice watching the gas level increase on a 30 mile trip home! I have not changed the pump in this unit since I bought it with 143k over 3 years ago(203k currently)but the seller showed me receipts that it was done at 120k and the intake done at 130k,heater core @ 135k and the multi function switch at 140k-anyway I just keep track of my miles traveled,anything over 250:get gas!

 

ya it just sucks not knowing how much gas you have though especially when you drive as much as i do

 

i use the trip function on the odometer. like step66 said anything over 250-275 get gas lol sucks but as soon as you clean up or replace the sending unit / pump it will return to normal operation