1999 Blazer Gas Gauge Reads Empty!!

Hello, I have a few problems I need help with. I recently bought a 1999 Chevy Blazer LS 4wd 4.3. First of all, the gas gauge is always reading empty, and the low fuel light is on. The guy I bought it said it has been like that since the new motor was put in. I've posted several threads on yahoo, and everyone was telling me that it was the sending unit, so I had that changed, and needless to say its still not working.:banghead: Any suggestions on what else this could be...ohh I did have the codes read at autozone before pump was put on, and when they reset the codes, the fuel gauge went up to full, light went off for about 10 seconds, and then back. ... And next question, the other day I pulled into my driveway, and the truck stalled, I tried to start it and it just rolled over, and over. I shut key off, and tried again...the 3rd time, i pumped the gas pedal twice...and it started right up...did it again today..didn't start until i pumped the gas...What would cause this???? PLEASE HELP!!:screwy:

Hello, I have a few problems I need help with. I recently bought a 1999 Chevy Blazer LS 4wd 4.3. First of all, the gas gauge is always reading empty, and the low fuel light is on. The guy I bought it said it has been like that since the new motor was put in. I've posted several threads on yahoo, and everyone was telling me that it was the sending unit, so I had that changed, and needless to say its still not working.:banghead: Any suggestions on what else this could be...ohh I did have the codes read at autozone before pump was put on, and when they reset the codes, the fuel gauge went up to full, light went off for about 10 seconds, and then back. ... And next question, the other day I pulled into my driveway, and the truck stalled, I tried to start it and it just rolled over, and over. I shut key off, and tried again...the 3rd time, i pumped the gas pedal twice...and it started right up...did it again today..didn't start until i pumped the gas...What would cause this???? PLEASE HELP!!:screwy:

What type of pump/sender unit?

Get a fuel pressure gauge (~$20.00 for a cheap one) and tell us what your pressure is with key on, engine not running; engine idling, and how long it retains pressure after you shut ignition off.

Check the fuel pressure as stated, but also check the ign system. If you have to pump or hold down the gas to get it to fire it may be flooding. When the gas is pressed about 80% or more the car enters a "clear flood" mode. As for the fuel gauge, I do not remember, but I think reading empty means a short to ground. It may mean open, but I think open will read full. Check out the harnesses to make sure no wires are pinched. And it wouldn't hurt to check the grounds involved either.

Did you install just a sending unit or did you replace the pump too?, and did you install a acdelco unit. Did you test your fuel pressure when your truck stalled and if you hadn't you should of. Aftermarket fuel pumps are trash and don't last, when it comes to these trucks you should put in a acdelco pump only, otherwise your just asking for trouble. I replaced my hole unit with a acdelco pump and sending unit when my gas gauge stopped working, so I killed two birds with 1 stone.

Wow...urs looks just like mine...and its crazy u responded....I'm from Owosso, Mi..Born, and graduated...and..I did replace whole unit...pump, and sending unit.

Wow...urs looks just like mine...and its crazy u responded....I'm from Owosso, Mi..Born, and graduated...and..I did replace whole unit...pump, and sending unit.


Small world huh Mike. You didn't mention what brand of fuel pump you had installed? Also it's a good idea to leave your fuel pressure gauge hooked up taped to your windshield and monitor what your fuel pump is doing. When mine was going out I had mine taped to the windshield for a solid week. If you had anything other than acdelco installed I would still suspect the fuel pump until it was ruled out especially if your gas gauge still doesn't work. Our trucks need a bare minimum of 60 to 65 psi to run right. Also when your fuel pump was changed did he install the new connector/plug? Don