For whatever reason you come to a stage where you need to adjust your idle, here are the correct procedures.

Extracted from Helms workshop manual - Thanks Tek!

1. Start the vehicle and let it warm up to normal operating temperature. Cooling fan should come on.
2. Connect a tach gauge.
3. Disconnect the 2P connector on the IACV unit. (Refer to Fig 1.1)
4. Adjust the idle screw on the throttle body. B16a engines - with no load, the idle should be 700rpm +/-50rpm. (Refer to Fig 1.2)
5. Turn the engine off.
6. Re-connect the 2P connector on the IACV unit. Reset the ECU by removing the fuse under the hood for 30 seconds.
7. Restart the vehicle again with no load. The idle should now be the figure you set previously in step 4.

Fig 1.1

Fig 1.2

Throttle Position Sensor (TPS) Adjustment

Most probable causes of inconsistent and fluctuating idle are vacuum leak(s) and faulty TPS voltage output. Here are the correct procedures for the TPS adjustment.

1. Follow the wiring harness from the TPS to the back of the intake manifold and remove it from the firewall. This will give you more room to probe the electrical terminals. (Refer to Fig 1.1)
2. Turn the ignition to the 'on' position. Using a voltmeter, check the voltage from the TPS electrical connector. It should read approximately 5.0 volts.
3. With the throttle fully closed and TPS connector connected, connect the probes of the voltmeter to the positve and ground wire. It should read approximately 0.5 volts with the throttle valve fully closed.
4. Slowly turn the throttle valve and see if the voltage changes as the sensor travels from idle to WOT. The voltage should increase smoothly to approximately 4.5 volts.