I have a 99 Chevy Blazer LT. I parked it after running out of gas on a Friday 4 weeks ago and putting gas into it to get it home, I went out on Sunday afternoon to go somewhere and it would not start. You can here the fuel pump running when you turn the ignition key to turn over but it wont start. I replaced the battery, the fuel filter, poured fuel into the top. When I poured fuel in it would run just enough until the fuel ran out. Then to make matters worse......When I got out of the car it started to try and start on its on. My key fob is dead so it inst that I pressed something. This has happened 3 times......trying to start.....lights flashing and bells and whistles going off like it is setting off alarm of some kind. Any suggestions ?

 

looking around on here, you will note the first step is to get a fuel pressure test gauge and see what the priming {key on} pressure is, should be about 60 and note how long it takes to drop to 50.

No way around it.

But the other symptoms suggest either an ignition switch problem or maybe aftermarket entry/ starting system?

Since the thing will run when you add gas, doesnt look directly related.

 

I had this happen before. What you need to do is turn the key on, but not the engine. Turn it off then on again...do this repeatedly until your sick and tired of it. Try to start it, if it doesn't work do it again.

The fuel pump sends fuel into the line, what this will do is fill the line. When you drain the tank and change a fuel filter it empties the line. Try this, let me know. Works for me every time.