NOTE: For wiring diagrams, see WIRING DIAGRAMS article in the ENGINE PERFORMANCE Section. For vacuum diagrams, see VACUUM DIAGRAMS article in the ENGINE PERFORMANCE Section.

Turn ignition off. Remove ACG fuse in underdash fuse box for 10 seconds to reset ECU. Start engine, and allow cooling fan to come on. Road test vehicle. Connect jumper wire to diagnostic connector. Observe CHECK ENGINE light. If light does not flash, problem is intermittent.
If CHECK ENGINE light is flashing Code 45 and/or 46, turn ignition off. Test fuel pressure regulator. See BASIC TESTING article in the ENGINE PERFORMANCE Section. Repair as necessary.
If fuel pressure is okay, install a known good MAP sensor. Repeat step 1), and recheck for code(s). If code 45 and/or 46 is still present, go to next step. If codes are not present, install a new MAP sensor.
If Code 45 is present, install known good injectors to left side of engine. If Code 46 is present, install known good injectors to right side of engine.
Repeat step 1). If code(s) is still present, substitute a known good ECU, and retest system. If problem goes away, replace ECU. If code(s) does not appear, replace injectors.

When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

• You smell fuel, burning insulation, or see smoke.

• Brakes feel soft, pull hard to one side, or make grinding noises.

• The engine overheats, stalls repeatedly, or misfires under load.

• You are missing required tools, torque specs, or safe lifting equipment.

• You are not confident in the next step or safety outcome.

Safety Warning

Code 45, Code 46: Fuel Metering System

Use the Manual With the Right Hardware

When to See a Mechanic

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