Is this a Passlock problem?
 

I am working on my nieces '99 Alero. It has just started having a starting issue. I've read a little bit on the Passlock system, and this sounds like what her issue is.

Here is what happens. When it isn't starting, I noticed, aside from the usual lights, the fuel gauge will be at empty when it wont start, even though it has about 3/4 tank full. Then when it finally starts, after cycling the key a few times, the gauge registers normal. Just trying different things, I turned the key on and left it on, the gauge didn't move and fuel pump didn't come on, then after between a minute to 10 minutes the gauge would go to the current level and the fuel pump would come on.

At first, I figured it was something to do with the sending unit in the tank being faulty, but after finding out how much it was, I wanted to research further. If this is a Passlock problem, which system is it, 1 or 2? I'm assuming 2 if there is no chip in the key. I had a '89 Camaro with chip, and bypassed the VATS when I swapped from FI to a carb engine.

So, does this sound like the Passlock system being faulty? I need to get her car done soon since she starts back to school tomorrow. Thanks for any help!

When Passlock prevents the car from starting, the security light on the dash will flash. The fuel pump will run until pressure builds up, but the PCM will not allow fuel to the injectors. The engine will crank but not start. See the Passlock sticky thread at the top of the Alero page.

Your problem sounds like the ignition switch is going bad. It's a common GM failure.