Intake Air System (Hatchback): Diagnosis Honda Civic VII рестайлинг

Throttle Body Test

Note. Do not adjust the throttle stop screw. It is preset at the factory. If the malfunction indicator lamp (MIL) has been reported on, check for diagnostic trouble codes (DTCs) (see GENERAL TROUBLESHOOTING INFORMATION ).

1. With the engine off, check the throttle cable movement. The cable should move without binding or sticking. If the cable moves OK, go to step 2. If the cable binds or sticks, check it and its routing. If the cable is faulty, reroute it or replace it and adjust it (see «THROTTLE CABLE ADJUSTMENT»(ref-172063-S07983041232005021800000) ), then go to step 2.
2. Move the throttle lever by hand to see if the throttle valve and/or shaft are too loose or too tight. If there is excessive play in the throttle valve shaft, or any binding in the throttle valve at the fully closed position, replace the throttle body. If the throttle valve and shaft are OK, go to step 3.
3. Connect the HDS or a scan tool to the DLC.
4. Turn the ignition switch ON (II).
5. Check the throttle position with the HDS or a scan tool. The reading should be about 10% when the throttle is fully closed and about 90% when the throttle is fully opened. If the throttle position is correct, the throttle body is OK. If the throttle position is not correct, replace the throttle body.

Intake Air Bypass Control Thermal Valve Test

Special Tools Required

Vacuum pump/gauge 0-30 in.Hg A973X-041-XXXXX

Scheme 210

1. Start the engine. Then let it idle. NOTE: The engine coolant temperature must be below 149°F (65°C).
2. Remove the vacuum hose (A) from the intake air duct, and connect a vacuum pump/gauge to the hose.
3. Raise and lower the engine speed, and make sure the vacuum gauge reading changes as the engine speed changes. If the vacuum reading does not change, check for these problems: Misrouted, leaking, broken, or clogged intake air bypass control system vacuum lines. A cracked or damaged intake air bypass control thermal valve.
4. Hold the engine at 3,000 rpm with no load (in neutral) until the radiator fan comes on, then let it idle.
5. Raise and lower the engine speed, and make sure the vacuum gauge reading does not change as the rpm changes. If the vacuum reading changes, check for these problems: Misrouted, leaking, broken, or clogged intake air bypass control system vacuum lines. A cracked or damaged intake air bypass control thermal valve.

Scheme 211

1. Remove the nuts (A) and the stud (B).
2. Remove the air cleaner (C).
3. Install in the reverse order of removal.

Scheme 212

1. Disconnect the PCV hose (A).
2. Open the air cleaner housing cover (B).
3. Remove the air cleaner (C) from the air cleaner housing (D).
4. Install in the reverse order of removal.

Scheme 213

1. Check cable free play at the throttle linkage. Cable free play (A) should be 10 12 mm (3/8 1/2 in.).
2. If the free play is not within spec (10 12 mm, 3/8, 1/2 in.), loosen the locknut (B), turn the adjusting nut (C) until the free play is as specified, then retighten the locknut.
3. With the cable properly adjusted, check the throttle valve to be sure it opens fully when you push the accelerator pedal to the floor. Also check the throttle valve to be sure it returns to the idle position whenever you release the accelerator pedal.

Scheme 214

Scheme 215

Scheme 216

1. Fully open the throttle valve, then remove the throttle cable (A) from the throttle link (B).
2. Remove the cable housing (C) from the cable bracket (D).
3. Remove the throttle cable (A) from the accelerator pedal (B).
4. Install in the reverse order of removal.
5. After installing, start the engine. Hold the engine at 3,000 rpm with no load (in neutral) until the radiator fan comes on, then let it idle.
6. Hold the cable, removing all slack from it.
7. Set the locknut on the cable bracket (A). Turn the adjusting nut (B) so that its free play is 0 mm.
8. Position the adjusting nut on the other side of the bracket (A), then tighten the locknut(C).
9. With the cable properly adjusted, check the throttle valve to be sure it opens fully when you push the accelerator pedal to the floor. Also check the throttle valve to be sure it returns to the idle position whenever you release the accelerator pedal.

Scheme 217

1. Remove the intake air duct (A).
2. Disconnect the connectors from the IAC valve (B), EVAP canister purge valve (C), MAP sensor (D), and TP sensor (E).
3. Disconnect the water bypass hoses (F), and plug the water bypass hoses.
4. Disconnect the vacuum hoses (G).
5. Remove the throttle cable (H) and the actuator cable (with cruise control) (I).
6. Remove the throttle body (J).
7. Install the parts in the reverse order of removal with a new gasket (K), then recheck these items: Do not adjusting the throttle stop screw (L). Do the ECM idle learn procedure after throttle body has been replaced (see «ECM IDLE LEARN PROCEDURE»(ref-172050-S39748332772005021800000) ). Refill the radiator with engine coolant (see «COOLANT REPLACEMENT»(ref-171331-S01157056062005020200000) ).

Scheme 218