The O2 sensors that your codes flag are not involved in engine operation. They only check the effectiveness of the catalytic converters for emissions requirements. The IMRC valves are normally closed, but open at high RPM. They could cause idle issues if they are stuck open. I'm surprised you don't have a OBDII code that flags the IMRC issue.
The intake air temp sensor would also be an issue worth exploring. Although it is not as important as the MAF sensor, it does influence the PCM fuel mixture calculations.
You might try looking at the website obd-codes dot com. It has diagnostic guides that could help you determine the source of the code (sensor, wiring, other).
It can be very helpful if you can get a scan tool to read the fuel trim levels... vacuum leaks are common, especially on older vehicles. Vacuum leaks will show up in the scan tool fuel trim data before a code is set, especially at idle since the rpm is low and manifold vacuum is high.