Hello. i have a 2000 chevy blazer with a fuel guage problem. a few months ago i noticed the fuel guage started to jump all over the place. it went from a full tank down to empty and back to a 1/2 tank. a few weeks after that the fuel pump went on me. at the time it made sense because i figured the sending unit wich is part of the fuel pump would correct my fuel gauge problem. wrong. i installed a new fuel pump that cost me 300$. before i put the new unit in the tank i made sure the fuel guage went from full to empty by manually moving the arm on the sending unit. it worked ok at the moment. so now i have my sending unit/ fuel pump in the tank and installed back in my blazer. before i put fuel in the tank i again made sure the guage read empty and it did. i watched the guage as i had the tank filled and it went from empty to full. as i started to drive again i noticed the fuel guage would not go below 1/4 tank. i figured it would somehow reset itself. it didnt. this went on for about 6 or 7 tanks of fuel now the guage reads empty and my fuel low light stays on even with a full tank of gas. every couple of weeks the guage will jump to what seems to be the correct level for a short period then it goes back to empty. i would like to get some input on this problem before i drop the tank again. bad guage? sending unit? i dont know.

 

I also have a 2001 Blazer and it does the same thing. It always goes from empty and showing the low fuel light to full for no reason. I have also inquired about this problem. It could be the sending unit which is in the tank or it could be the guage it self. Both of these are very expensive to replace. I think the dealer quoted me close to 300 bucks for the guage cluster. Im hoping it is something else. If you have had any progress on this could you please post. Thanks.

 

my 99 s10 does the same thing, never gets past 1/4 tank and then rises up to about 3/4 tank before it gets empty. ive gotten used to drive with a gas can. but i do remeber talking about this with some other members, and a possible reason. so search for some threads on this, cause it seems to be a common problem in these trucks.

 

It sounds like a fuel pressure sender problem. This is the only thing I could find, but I don't think it properly describes your problem.

Condition/Concern:
Fuel gauge may be inaccurate or drops to empty (E) and the low fuel light comes on. Further analysis may reveal that this condition is most apparent when the gauge is at or below the quarter (1/4) tank mark.
Recommendation/Instructions:
Try to duplicate the concern by driving the vehicle a short distance in reverse and then stopping (to make fuel slosh), shifting transmission to park or neutral and then shifting to drive. The fuel gauge will have a tendency to read lower than actual. The gauge will take a few minutes to show the actual fuel level. The VCM/PCM is the buffer for the fuel gauge.
[ol]On a Automatic Transmission no buffering takes place when the transmission is in park or neutral. This is a NORMAL characteristic & NO repairs are necessary.
On a Manual Transmissions, the fuel gauge is buffered in all gears and neutral. Since the VCM/PCM has no way to know what gear it is in, there is a timer which starts to count up when the clutch is depressed. When this timer reaches its calibrated value (this value will vary), the filtering switches to the "fast" filter (no buffering). When the clutch is releases the filter then switches to the slow filter (system is Buffered). This is a NORMAL characteristic & NO repairs are necessary. [/ol]

 

my 99 was not always like this. yea while shifting gears i did get a little play in the gauge but this is now terribly worse. it has a demonic possesion, thats how messed up it is. mine deffinitly needs repair. im just wondering if its the gauge but i think its in the sending unit/tank.

 

Mine has low fuel light come on, but if you open the driver's door, the light goes out. Guage is accurate between full & 3/4 tank. I use trip odometer, it's always accurate, except when my wife doesn't keep an eye on it. But then, ya gotta watch the guage too or you'll run out.
I know the sending unit is bad, but for the $$$, just live with it.
BTW, I Seafoamed yesterday - man, I think I took 1 year off the life of the planet[:'(]phew!Engine idles better, not sure on mileage yet.

Doug

 

I had the same problem when I bought it. It is the whole fuel sending unit. Ipaid almost 600 for theunit,you can find themonline for like400.I just got mine installed at the shop and it came to like 850+ taxes. Its alot of labour as you know cause you have to drop the fuel tank etc. But im glad I forked out the cash to do it, I get no movement of the gauge now and its very accurate, I get no jumping around. Im the type of person that can't rely on the trip meter.