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Interesting study here.....
2005 Pontiac Grand Prix, 3.8, no supercharge
260,000 miles
Wife went to work, came out and it would not start. Towed home, changed plugs and wires, fired right up no problem. Next day, wife drove it to work, it stalled out halfway there going up a hill. I got it to start, and it idled fine--but as soon as I began to drive it, went up an incline and it immediately stalled out. Towed home again.
I have replaced plugs, wires, fuel pump/filter in gas tank, crankshaft positioning sensor, ICM and checked the battery and alternator at auto repair store with no problems noted on bench testing. Charged the battery up just to be sure; still cranks but no start. It turns over, but just will not catch. Tester on the plug wire is not turning the light on, indicating the plugs are not getting spark. I also checked the 4 grounding wires (2 locations under the air filter area) and both are free of corrosion. There is a little oil moisture and some dirt, but nothing corroded and the wires look good.
Check power at pink wire and ground circuit. If both good, Make sure you have good cam and crank sensor square waveforms going into module
The ignition control module right below coils. I highly doubt you lost an ignition coil that will usually only cause loss of spark on 2 cylinders
Attachment has two diagrams that should help. On this system. Both cam and crank sensor waveforms should 12v waveforms(or battery voltage with engine running). Any labscope should get you a quick answer. But more then likely you have lost the ignition control module