Help! Fuel gauge is going crazy

2002 Blazer LS       I've been having problems with my fuel gauge & low fuel indicator when it gets down to about a 1/4 tank. - driving cross country or just from work to home - you can start the vehicle and sometimes you may 1/4 tank and the next time it will show low fuel and gauge will read E or below- then shift into neutral and it will pop back up to 1/4 tank. slaming on the brakes & side to side turns will not correct, only shifting to neutral.  Sometimes backing up will also cause this to happen.  The vehicle is still under extended warranty and the dealership hasn't fixed it yet. Has anyone had simular issues or know of this?  Thanks for any help / information

i have a 99 s10 that has a similar problem, the gauge is all over the place when i actually get low. untill then it just shows me as being low and my light doesnt always work.  i dont know what causes this but several posts have been made to try and figure it out. i am assuming its a bad sending unit in the tank.

The putting it in neutral changing the reading thing has me thinking that maybe you have a wire pinched somewhere by the shift linkage.  I would get under there and check the wiring harness to the tank and make sure that it isn't damaged.

As far as inaccurate readings.  I find that if I park on a hill, my reading is screwy for the first few minutes of driving, but settles back.  These sending units are picky in these trucks.

The dash was replaced and I'm on sending unit 3 or 4 - thanks  for the ideas - If the dealer fixes it I'll post what was found.

Sending unit.
 
Are you ready for sticker shock?
 
your looking at about $250-$350 to replace it. Its part of the fuel pump assembly and you ahve to replace the whole thing as one unit.

My 02' did the same thing, the dealer replaced the sending unit  and it work for a little while, but has since (7 months) reverted back to its old ways.  Be sure to post what they find, I may be getting a new unit as well.

quote:

ORIGINAL: Hanr3

Sending unit.

Are you ready for sticker shock?

your looking at about $250-$350 to replace it. Its part of the fuel pump assembly and you ahve to replace the whole thing as one unit.

 
Hanr3: The parts are available seperately if you want to do the job yourself but dealers are forcing people to buy a part that they won't need until it fails...I have found them on E-Bay for $30 - $50, AC/Delco web site has it for $70+.
 
Dealer will replace these parts seperately while the vehicle is under warranty so why not after???.....$$$$$$$$ cash cow...

Well the dealer offered this - It's normal to act this way at ofr below 1/4 tank.  Just fill it up when it gets down near a 1/4 and don't shift to nuetral while your moving and you won't have this problem. A technician also informed me that the ECU  has a part in the fuel gauge reading( it locks out the the sending unit when the gear selector is shifted to nuetral or park something to do with anti-sloshing) I was also told that the gauge should at sometime start working again correctly once it has been locked out but not quite sure how long it may take - couple minutes, till you run out of gas, you fill the tank above 1/4, you restart the car, or when ever it feels like working again - IT"S NORMAL for this vehical to act like this.  I'm told - I guess it's to much to ask for a gas gauge that works on a 2002 year vehical.  - Thanks for your guys help  - Does anyone have an in with Chevy to verify this?

that is a bunch of crap, I can't stand that /w my truck. Sometimes I'll only put in a few gallons @ the gas station and soon as I pull out it reads empty and the low fuel light comes on.  When I come to a stop and put the car into park it then reads correctly.  So were just supposed to live with this defect? I'm going to talk /w my dealership and see what they say.

Never mind.

It was explained to me that it is something in the ecm that will block the signal from fuel sensor it help with fuel gauge needle bouncing around.  I noticed it also on my 02 Montanna.  Not much your going to do now except keep it filled above 1/4 tank.  It's not the answer I want to hear.

Guess at some point I will have to change the sending unit.

#1 Cut the freakin' language.

#2 Please do not post in caps. 

#3 You resurrected a thread that is over a year old for what???  Just to rant and rave??  What a waste.

Now, the actual problem is the sulfur in the fuels coating the sensor grid.  Complain about the fuel!  Dodge, Ford, GM, Toyota, Honda, etc all have had problems of this type in this time period.  Some are better than others, but it comes right down to the fuel.  Run a fuel system treatment at every other oil change and I can assure you that you won't ever have a problem.  Once the grid gets coated, it is likely that it will never operate properly again.

About the access panel.  My Bonneville had one.  My Intrepid had one.  Many GM cars have them.  It really isn't that difficult to drop a tank (and yes, I have done a few...).  When you have no alternative, you add an access door.  Is there an access door in the bed of a Tacoma?  I think not.

If you need help, post about it.  But cut the crappy attitude!