I replaced my lower and upper intake manifold gaskets, and just got everything back together. I have headlights, radio, etc., so there is power. When I turn the key, I get one hesitation, the lights dim, and then nothing. No starter clicking or anything. The battery gauge showed it being right around 12 V, which should be enough to get some mild clicking even if it were low. It has a brand new battery, starter, and alternator.

The alternator is rigged up right now because the plastic connector broke. GM uses a 4 pin connection but the alternator only actually uses one of those pins. It is possible I connected it to the wrong pin, but even if I did would this prevent any clicking at all? This would be the power going to the alternator. A car should be able to start if the battery has enough juice even without an alternator installed (and then die quickly). The only reason I could see this affecting it is if for some reason it'* a bad ground. Can anyone verify which pin the alternator uses? I am using the third from the left (the one next to the bigger pin I believe).

Do the wires going into the ICM have to be in a specific order? I'm fairly positive they are the same as when I removed them, but there'* a small chance one got switched. The ones coming from the rear rotate every other with the ones from the front, with the rear starting on the top pin.

If I hold the key in the start position, I sometimes hear a faint whine, but only every couple of tries.

ALSO, I lost the keys during the repair process so I had to have the dealer make new door and ignition keys from scratch. I'm assuming the key is correct since it fits and turns. However, if the codes were wrong with this be a possible cause? They had to look them up by VIN. It'* much more likely that I forgot to reconnect something somewhere along the way.

Very open to troubleshooting suggestions.

the security lamp is not flashing while you turn the key to start is it?

I'd almost wager the battery is run down or tired, I would load test it and go from there.

It sounds like your car could be in security lockout. I'm not 100% sure. I'll PM Danthurs and see if he can help

I would start with cleaning both ends of both battery cables. Sounds a lot like corrosion.

The security light is lit when the key is turned, but that is typical from what I remember. Like I said, the voltmeter showed ~12 V. This should be enough for some clicks I would think. The headlights are still on very strong. But, the thought did cross my mind as well. I'll give it a charge tomorrow and see what happens.

I'm with Dan on the battery corrosion/cables. Your headlights etc will be bright and have a no start.

Thinking of the repairs you did.. that would be the likely thing that was touched and could cause the no start. Another might be coolant in the cylinders, however you'd get a click with that.

There is coolant in the overflow tank, but of course there will not be any in the cylinders until the car starts and cycles it through. The battery posts going into the battery itself are both brand new, so there is no corrosion there. I tried to clean most connections as I went because it was all oily due to the bad gaskets. What parts should I be checking the connections on specifically? Alternator would not prevent clicking, the starter was untouched. ICM? Bad ground somewhere?

(Still have not had a chance to try jumping it, purely speculation)

Check to see if you are getting voltage to the starter when the key is turned to start. If you are getting voltage to the starter, pull the starter and have it tested.

Understanding that the battery was new and clean. Did you happen to look at the cable ends where they connect to the battery? Corrosion is common on the cable ends, and has been found to hide under the cable boots and cable sheath.

While unlikel...I tossed the coolant in the cylinder out there because it can happen.
As part of doing the LIM gaskets, the LIM contains some coolant (even after system is drained). As we lift the LIM off the engine, it is possible to have some coolant go into the head and enter the cylinder through an open valve. the valve would be open based on when the engine stopped.

Really can't think of anything else that should keep the car from turning over. You could check the voltage at the starter, ground at the engine block and then test the starter soleniod wire for power when the key is turned to start.

I tried jumping the battery and it charged up to ~13 V and still same issue. The starter was just put in this month. I would be very surprised if it were bad, but I will check the voltage. I do hear a whining though when I hold the key, as if the shimming is off. However, seeing as how it has been working until now, it'* not possible the shimming is incorrect. Could it be something with the drive belt? I will check the voltage going to the starter when I get a chance.