Cars of that era will shut off a specific injector if the computer detects a repeated miss fire. This is done to prevent raw fuel from damaging the cat converter.

Timing chain issues won't cause this problem.

Ignition coil / plug wires are a common source of a missfire in higher mileage cars of that era. Reading the trouble code then swapping coils and wires around will help in pin pointing the failed part. Be sure to change the spark plugs as well if they have more than 40 K miles.