Why wont my 1996 Pontiac Bonneville start?

[check your starter. that was the problem with mine. 94 G20] Original Answer

We just fixed my sister's '95 G20 start problem and ours was a recessed pin in a connector in the starter relay wire (the small wire that's attached to the starter). but there are a few tests you can do;

1. This one is simple: make sure everything is hooked up like you were going to start it on a normal day, then turn your headlights on and try to start it. If it sounds like it tries and the headlights dim (even a little) it's likely a dead battery. if there's a click/no click and then nothing and headlights don't dim, you've got an open somewhere in the starter circuit.

2. If the engine cranks over no problem, but just won't start firing and driving itself, you've likely got either a dead fuel pump or a clogged fuel line/filter.

3. have someone listening under the hood when you turn the key to the on position to make sure the clutch inhibitor relay is clicking (should click once when the key is turned to the on position).

If you're a Do-It-Yourselfer, here's some solutions you can try. If not, take it to a mechanic and tell him/her your findings and let them go from there.

1. If you have a multimeter/voltmeter and ohmmeter, you can investigate an open fairly easily-BE CAREFUL with the voltmeter test as you will have to have the battery plugged in. start by pulling the starter fuse (if it's like my sister's, it'll be tucked underneath the front driverside quarter panel under the hood, (should be able to access it just behind the battery). you can do an ohm test on the fuse itself to make sure it's good (if it's not transparent, otherwise just look at the metal arch inside it to see if it's separated). then a voltage test with the red lead in one side of the fuse plug and the other on the negative side of the battery or a good ground like the frame or the engine; you should get 11.9v-12.4v. (if you don't get voltage try moving the red lead to the other side of the fuse plug). Do you get voltage? Yes: your issue is farther down the line, closer to the starter motor. No: you have an open between your battery and the fuse. continue testing this way all the way to the starter motor. once on the other side of the ignition switch you can switch to ohm testing, just make sure the key is in the OFF position or you'll fry your tester. Here's a couple wiring diagrams for manual or automatic transmission: