Because I have been too busy to do it myself, I just had a bunch of work done on my '96 2.2 (5 speed) OBW:
Timing belt and associated parts (seals, water pump, thermostat, ect.)
New front 02 sensor
New knock sensor
New plugs and wires
New PCV valve
Before the work, the CEL was on and the computer had PO420 (catalyst) and PO325 (knock sensor) codes. Once the two sensors were replaced, the CEL turned itself off after the usual number of starts. But, ever since the work, the car has had a surging idle. It will almost die, then rev up to 1k RPM, then almost die again- in about 1 second cycles.
Any ideas? Maybe MAF or IAC? Other than the wonky idle, it runs and drives just fine and gets the usual fuel mileage (about 26 with oversize snow tires).