Engine Controls - Basic Testing - 2.7L: Diagnosis Honda Accord V

VISUAL INSPECTION

Visually inspect all electrical wiring for chafed, stretched, cut or pinched wiring. Ensure electrical connectors fit tightly and are not corroded. Ensure vacuum hoses are properly routed and not pinched or cut. See VACUUM DIAGRAMS - 2.7L article to verify routing and connections. Inspect air induction system for possible vacuum leaks.

Basic Diagnosis

Begin basic diagnosis of fuel system by determining fuel system pressure. If fuel pump fails to run, inspect power supply to main relay. If all power supplies are present (i.e., battery, ignition and starter switch during cranking), perform functional test of main relay. See WIRING DIAGRAMS at the end of this article, and SYSTEM/COMPONENT TESTS - 2.7L article.

Scheme 132

1. Disconnect negative battery terminal. Release fuel pressure. See «FUEL SYSTEM PRESSURE RELEASE»(ref-15919-S05656602412000122900000). Connect Fuel Pressure Gauge (07406-0040001 ) at 6-mm bolt. Reconnect negative battery terminal. Start engine, and note fuel pressure. If vehicle will not start, check for spark. If spark is present and no fuel pressure is evident, inspect fuel pump main relay.
2. Remove connector from fuel pump main relay. (Scheme 132) Using a test light, check power on Black/Yellow wire at fuel pump relay connector. If power is present, go to next step. If power does not exist, repair open wire between fuel pump main relay connector and fuse No. 2 on fuse box. Go to step 4).
3. Connect jumper wire between Black/Yellow wire (B+) and Red/White. If fuel pump runs, go to next step. If fuel pump fails to run, see «SYSTEM/COMPONENT TESTS - 2.7L»(ref-15921) article.
4. Start engine. Disconnect vacuum hose from pressure regulator, and check for manifold vacuum. If vacuum is not present, check for restriction in vacuum port or hose. Plug vacuum hose and inspect fuel pressure gauge reading. Gauge reading should be within specification. See «REGULATED FUEL PRESSURE»(ref-15919-S24695893272000122900000). Pressure should drop slightly when vacuum hose is reconnected.

REGULATED FUEL PRESSURE

See also:
• ADJUSTMENTS - 2.7L