Throttle Body Test; Intake Air Bypass Control Valve Test - Honda 2002 Accord Manual

Intake Air System
Throttle Body Test
NOTE:
• Do not adjust the throttle stop screw, It is preset at the
factory.
• If the Malfunction Indicator Lamp has been reported
on, check for Diagnostic Trouble Codes (DTCs) (see
page 11-3).
1. With the engine off, check the throttle cable
operation.The cable should move without binding
or sticking.
• If the cable is OK, go to step 2.
• If the cable binds or sticks, check it and its routing.
If it's faulty, reroute it or replace it and adjust it
(see page 11-134), then go to step 2.
2. Operate 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 a scan tool to the Data Link Connector.
4. Turn the ignition switch ON (II).
5. Check the throttle position with the scan tool. There
should be approx. 10% when the throttle is fully
closed and approx. 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 Valve
Test
1. Hold the engine at 3,000 rpm with no load (in Park
or neutral) until the radiator fan comes on, then let
it idle.
2. Disconnect the air assist hose (A) from the IAC
valve (B) then connect it to a vacuum pump/gauge
<C).
3. Start the engine, then let it idle.
4. Check the vacuum.
Is there any vacuum
Y E S - G o to step 5.
NO—Repair the air assist hose. •
5. Disconnect the air assist hose from the vacuum
pump/gauge, then connect the air assist hose, the
IAC valve and the vacuum pump/gauge by using a
three-way joint (D).
6. Disconnect the IAC valve 3P connector.
7. Check the vacuum.
Is there vacuum above 40 kPa (300 mmHg, 12 in.
W
Y E S - R e p l a c e the IAC v a l v e . •
IMO —The intake air bypass control system is OK. •
11-132