Oldsmobile/Buick Repair: 88 Olds Ciera Wont Start, crankshaft damper pulley, crankshaft position sensor

Question
Hey I have a 1988 Oldsmobile Ciera that won't start. It started acting up a few weeks ago when I heard a rattling noise in the front that grew louder and softer with the RPMs. Then it started idling high. Finally the engine was chugging as I was driving down the road. Now it won't start altogether. It just sounds like something isn't firing. When I turn the key partway I can hear the fuel pump run. The only thing I have done so far is the paper clip trick to see if I got any OBD codes but the only number that came out was 12 which I understand to be normal. Any help here would be greatly  appreciated. Thanks a lot. John

Answer
Hi John,
First, I would like to know if the engine cranks over, that is, turns with the starter.
If so, and you think the rattling was from near the front of the engine, I would look near the crankshaft damper pulley, and see if there is a crankshaft position sensor, or the damper itself loose.

The timing chain is also a possibility if the rattling was from inside the front of the engine, and the car has a lot of miles on it.

Van