Ok. This code can be set simply because the timing chain has become loose over the miles. At 160,000 that is where I would focus. These things are real bad about Crankshaft Sensors too. See the chart I have loaded at the bottom for you. Tells exactly how to check.
Check the chain and crank sensor first!
You can remove the distributor cap, and while moving the crankshaft by hand, you can take a look at how far the crankshaft is able to move before the distributor begins to move. That is how I personally check this engine. Should only move a few degrees before the distributor rotor moves.
Here are a list of other Diagnostic Aids that you can look at.
The check following items:
- A loose or missing distributor hold down bolt.
- A loose CMP sensor causing a variance in the sensor signal.
- An incorrectly installed distributor-1 tooth OFF in either advance or retard positions.
- A loose distributor rotor on the distributor shaft.
- Excessive free play in the timing chain and gear assembly.
An intermittent may be caused by any of the following conditions:
- A poor connection
- Rubbed through wire insulation
- A broken wire inside the insulation. Thoroughly inspect any circuitry that is suspected of causing the intermittent complaint. Refer to Testing for Intermittent and Poor Connections in Diagrams. If a repair is necessary, refer to Wiring Repairs or Connector Repairs in Diagrams.
Additionally there are some Tests you can perform with a scan tool to check Camshaft Retard Offset. See the Chart Below.
Hope this will give you the information you need.
Thanks and have a great day.