- Run the engine to normal operating temperature.
- Clamp the air injection hose before the relief valve.
- Turn the flowmeter bypass screw all the way in.
- Connect a tachometer to the engine.
- Turn the throttle plate housing screw to obtain an idle speed of 850 rpm.
- Back out the flowmeter bypass screw until the idle speed drops by 50 rpm.
- Unclamp the air injection hose. The idle speed should fall within specification by 50 rpm either way. If not, obtain the correct idle speed by turning the throttle housing screw.
- Start the engine and allow it to come to operating temperature.
- Connect a tachometer to leads D1-1 and D1-3 of the diagnostic connector (shown as 1 & 3 in Fig. 33).
- Turn all accessories off. Wait for the electric fan to shut off.
- Turn the throttle plate bypass screw to obtain the correct idle speed.
These cars use Throttle Body Injection. Idle speed adjustment is necessary only if the Idle Speed Control (ISC) motor has been replaced.
- Remove the air cleaner.
- Start the engine and allow it to reach normal operating temperature. Make sure that the A/C control is off.
- Connect a tachometer to terminals D1-1 and D1-3 of the diagnostic connector (shown as 1 and 3 of Fig. 33).
- Turn the engine off. The ISC plunger should move to the fully extended position.
- Disconnect the ISC motor wire connector and start the engine.
- Engine speed should be 3,300-3,700 rpm. If not, turn the hex head bolt on the end of the plunger to obtain 3,500 rpm.
- Fully retract the ISC motor plunger by holding the closed throttle switch plunger with the throttle open. The closed throttle switch plunger should not be touching the throttle lever when the throttle is returned to the closed position. If contact is noted, check the throttle linkage and/or cable for binding.
- Connect the ISC wire.
- Turn the engine off for 10 seconds. The ISC motor plunger should move to the fully extended position.
- Start the engine. The engine should speed up to 3,500 rpm, stay there for a brief time, then drop off to normal idle speed as shown on the underhood sticker, and in the Tune-Up Chart.
- Shut off the engine, disconnect the tachometer and apply a penetrating thread sealant to the adjustment screw threads.