Faulty Fuel Gauge '99 Silverado

Aloha from Hawaii. I just bought a '99 tricked-out Silverado from L.A. (More on that later...) My fuel gauge just went on the fritz a few weeks back. When I start the truck the Low Fuel Warning light comes on and the fuel gauge reads empty. After a few minutes the fuel gauge slowly climes to the correct setting, but not for long. As I drive it will often fall back to the empty setting and the warning light will come on again. It will go thru this cycle several times; sometimes not even resting on the correct setting.

Any idea what is causing this to happen?

The problem is with your Fuel gauge Sending unit which is part of the Fuel Pump Assembly. You need to drop your tank and Replace the the Sending unit, This is a common problem with the 99'-01' Silverado's. Go

Good Luck.
-Jimmy

my 99 silverado did the same thing. dropped the tank and replaced the fuel gauge sending unit. works better than new!!!

I just got a 2000 Silverado this week and it's doing exactly the same thing, gauge goes to empty then comes back up to actual gas level. Glad to know how to solve the problem.

Does anyone know how difficult it is to drop the fuel tank and replace the gauge. I would want to replace everthing in there once I've gone to that trouble. Are there any special tools required to disconnect fuel lines etc? Thanks a bunch!

Mahalo (thanks) everyone!

Damn, I was hoping that was NOT the solution. I checked all the connections and was hoping a loose ground was the problem. I knew that dropping the tank was the final step. Really didn't want to do that.

I have the same problem in my '87 El Camino and know that the fix for that is also replacing the sending unit/pump in the tank....

Aside from my Silerado (that is Whipple equipped), I also have a '87 El Camino (super clean and 350 equipped), a "stock" '02 PT Cruiser, and a '95 Harley Electra Glide (stripped and w/a built motor.) I like my toys!!!!

my 98 Sierra's gas gauge vibrates and just flips backwards and forwards between F and E. I have been told it the fuel sending unit also. Must look into it soon.

its alot easier to unbolt the bed and move it back about two feet.check with this guy for your fuel pump assembly.i got mine from him for 180 shipped off of his ebay auctions.http://klova-autoparts.tripod.com/klova/id10.html

Anyone have the Delco part number for the sending unit or the rebuild kit I've heard about?

any one know what the part number is !

Here are the numbers for the whole unit with pump and sending unit.
Gm Part # 25176865 / 25345026
Ac Delco Part # Mu1089
Old Ac Delco Part # Mu86

Sonny

There was another post a while back that indicated there was a rebuild kit for the sending unit. Anyone know or have a part number on this.

My gauge dosent really do this yet. But it is starting to show signs of it. It will be at a 1/2 tank then 5 min. later i will look and i will be at 3/4??? Does this seem like i will have problems in the future? and is there anything i can do to stop it?

It's very likely that you will have this problem in the future. I just bought my truck from a small used car dealership last week and i'm already having the fuel gauge problems. Going today to finalize some paperwork so i'm gonna try and find out if i can get them to replace the damn thing for me.

Jake

If you purchased your vehicle from LA after 5/14/04 you probably got some bad Shell gasoline. Shell had an isolated problem with high sulphur content from one of their refinerys and the contaminated fuel was delivered to stations all over LA on that date, especially around the New Orleans area. Thousands of vehicle's sending units were damaged, including my wife's 1999 tahoe and my brand new 2004 Silverado. Shell paid for the sending unit replacement and gave every customer a $20 gas gift card, no questions asked. I don't know if the campaign is still active but here is the website that was posted in the newspaper that gave a list of participating dealers making the free repairs (www.interactclaims.com/shell/). You can also ask a Shell station attendant for the info.

Also have a '99 Silverado; just paid for the replacement ($525.00). Way too cold here to do it myself.
What I can't find - or find out - is whether the replacement pump and fuel level sending unit last longer than the original faulty ones?
Has anyone out there had a replacement in the truck for 4, 5, or more years without a recurring problem?
Probably won't get a reply to this one; if mine was fixed (and had continued to work) why would they be in a post about faulty fuel pumps?!?
Worth a try ...

this post is too old.....start new post of your own..

I was told you could not get the gas gauge unit by itself..that you had to replace both..I did and it lasted about 2 years now I need to have it replace again...Why is GM allowed to sell this crap and not have to replace it when so many are having problem with it..

I was told you could not get the gas gauge unit by itself..that you had to replace both..I did and it lasted about 2 years now I need to have it replace again...Why is GM allowed to sell this crap and not have to replace it when so many are having problem with it..

over the past few years this fuel guage reostat has improved .so 2 yrs ago you replaced this , because the gauge did not work ?


who did you purchase this fuel pump from ?

Everyone always mentions dropping the tank, why is that easier than removing the 4 bolts that hold on the bed, then carefullt li8ft and turn the bed enough to access and replace the pump and sending unit, granted you must be careful with any wiring for lights.

Everyone always mentions dropping the tank, why is that easier than removing the 4 bolts that hold on the bed, then carefullt li8ft and turn the bed enough to access and replace the pump and sending unit, granted you must be careful with any wiring for lights.

Depends on the equipment you have and help you have and what bed and mouting you have.

Some people even cut a acess hole in bed to get to the pump.

But main thing make sur it is the tank sending unit that is bad and then use the proper parts to fix it.
If replacing the whole fuel pump assembley always go Delphi.
Airtex and after market pumps are junk.

Everyone always mentions dropping the tank, why is that easier than removing the 4 bolts that hold on the bed, then carefullt li8ft and turn the bed enough to access and replace the pump and sending unit, granted you must be careful with any wiring for lights.

dropping the tank may or may not be easier..it depends on how much fuel in the tank. also what equipment you have to replace the pump.

advantage to sliding the bed back [not removing ] is , you can clean/lube the access to pump...install pump and test . measure voltages check wiring , fuel pressures , and grounds easier.. then slide bed back..


you need 2-3 guys to do this ..remove the rear tires..

I bought a 2001 Silverado 2 weeks ago and my truck has the same issue.

Seems as though when I top off the fuel gauge needle fluctuates less but when @ 1/2- 3/4 tank the gauge needle flucuates anywhere's between 1/4-3/4 a tank of gas while driving. Also, when parked and idling or if at a long red light the fuel gauge needle drops to empty and then the orange fuel light glows and stays on but as soon as I move the gear selector to drive the fuel gauge needle moves to about 1/2 a tank and the orange fuel light goes off .


Had me freaked out until after reading about the issue.
I pretty much keep track of my miles driven and gallons purchased until I can have it fixed.

the fuel sender was made with a silver material that reacts with the fuel.this causes the guage to go from full to empty,and every other point.

using techron fuel system cleaner along with 3 OZ of marvel mystery oil reduces this problem add when filling tank.

replacing the fuel pump is not easy.some have cleaned off this sender and found it to work good for a year or so.

these pumps are expensive. whatever you do do not use the airtex brand.

get the delphi fuel pump.

Great info guys.....thanks

I have the same problem with my 2001 Silverado fuel gauge of course. I was discussing it with my mechanic and he showed me one he had replaced. He indicated the problem is with the design of the sending unit in that the mechanism's arm that makes contact with the gauge plate does not have a tension setup built into it and when the edge of the arm making contact wears, it cannot make adequate contact therefore the sporadic readings. I was wondering why I couldn't just bend the arm a little to create more spring to it so it make better contact. Anyone have a reason why it wouldn't work?