GM cars of that era have an anti-theft device. The proper keys have a resistor with one of ten proper values embedded in it. If you have a key without the resistor (chip) in it, or the wrong value resistor, or if the anti-theft device malfunctions, the car will crank (turn over) but no fuel will be delivered.
Here's a test. Get a spray can of throttle body cleaner. Spray it into the air intake while someone tries to start the engine. If it starts and runs on the cleaner, then compression and ignition are good but no fuel is being delivered. That makes it likely that the anti-theft device is the problem.
If you know you have the wrong key, get the correct one. The dealer can cut the right one on a blank with the right resistor if you give him the VIN. You can find some detail online on the anti-theft device if you need to. It's not easy to override. On some GM models it sends a 5v 50 Hz square wave to the engine computer. If the computer doesn't see it, it stops the fuel injectors. You can't simply hotwire around it. The only way to fake it out is replace the anti-theft device with a 50 Hz oscillator. There's some information online on how to do that.
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GM cars of that era have an anti-theft device. The proper keys have a resistor with one of ten proper values embedded in it. If you have a key without the resistor (chip) in it, or the wrong value resistor, or if the anti-theft device malfunctions, the car will crank (turn over) but no fuel will be delivered.
Here's a test. Get a spray can of throttle body cleaner. Spray it into the air intake while someone tries to start the engine. If it starts and runs on the cleaner, then compression and ignition are good but no fuel is being delivered. That makes it likely that the anti-theft device is the problem.
If you know you have the wrong key, get the correct one. The dealer can cut the right one on a blank with the right resistor if you give him the VIN. You can find some detail online on the anti-theft device if you need to. It's not easy to override. On some GM models it sends a 5v 50 Hz square wave to the engine computer. If the computer doesn't see it, it stops the fuel injectors. You can't simply hotwire around it. The only way to fake it out is replace the anti-theft device with a 50 Hz oscillator. There's some information online on how to do that.
Change fuel filter.