Computers and Control Systems: Adjustments

Fig. 10 Throttle Cable Adjuster:

1. Start the engine and warm it to operating temperature (the cooling fan comes ON).
2. Connect a tachometer.
3. Check that the throttle cable operates smoothly with no binding or sticking.
4. Check cable free play at the throttle linkage.

Deflection: 0.39-0.47 in (10-12 mm)

5. If free play is not within specifications, loosen the lock nut and turn the adjusting nut until the freeplay is as specified.
6. Tighten the locknut and recheck the cable freeplay and if necessary readjust.
7. With the cable properly adjusted, check the throttle valve to be sure it opens fully when you push the accelerator to the floor. Also check that the throttle valve returns to the idle position whenever you release the accelerator.

Fig. 4 Electronic Air Control Valve:

8. Disconnect the 2 pin connector for the Electronic Air Control Valve.
9. Check the idle speed with no load on the engine (transmission in neutral, headlamps, air conditioning, blower fan, rear window defogger, radiator cooling fan and brake lamps all OFF).
Idle speed should be:

HF: 550+/-50 RPM
Si: 550+/-50 RPM

Fig. 5 Idle Speed Adjusting Screw:

10. If necessary adjust idle speed by turning the adjusting screw.
11. Turn the ignition OFF.
12. Reconnect the 2 pin connector for the Electronic Air Control Valve.
13. Remove the HAZARD fuse at the battery positive terminal for 10 seconds to reset the ECU.
14. Idle the engine for one minute with no load and recheck the engine idle speed.
Idle speed should be:

HF, 49 ST: 600+/-50 RPM in neutral
HF, CAI HIALT: 600+/-50 RPM in neutral
Si: 750+/-50 RPM in neutral or park

15. Set the parking brake and block the wheels.
a. MANUAL TRANSMISSION
Idle the engine for one minute in NEUTRAL with the head lamps on high beam and the rear defogger ON and check the idle speed.

Idle speed: 750+/-50 RPM

b. AUTOMATIC TRANSMISSION
Idle the engine for one minute in DRIVE and check the idle speed.

Idle speed: 700+/-50 RPM in neutral

16. Idle the engine for one minute with the blower fan ON (high speed) and air conditioner ON and check the idle speed.
Idle speed should be:

M/T: 750+/-50 RPM in neutral
A/T: 730+/-50 RPM in neutral or park

17. Cold engine idle speed is not adjustable.
If idle speeds are not within specifications refer to COMPUTERIZED ENGINE CONTROLS.