1. Verify the Main Relay Replacement:
* Correct Relay: Double-check that you installed the *correct* main relay. A wrong relay will cause similar symptoms. The relay should be clearly marked or have a part number that matches your car's specifications.
* Relay Socket: Inspect the relay socket itself for corrosion, bent pins, or damage. Clean the socket contacts with a contact cleaner and a small brush if necessary. Make sure the relay is firmly seated.
2. Check the Battery and Cables:
* Battery Voltage: Test the battery voltage with a multimeter. It should be around 12.6 volts when the car is off and slightly higher when the engine is running. A weak or dead battery is a common culprit.
* Battery Cables: Inspect the battery cables (positive and negative) for corrosion, looseness, or damage. Clean the terminals with a wire brush and battery terminal cleaner if needed. Make sure the cables are securely connected.
* Ground Connections: Check the ground connections on the engine block and chassis. Corrosion on these can prevent a good electrical ground path.
3. Inspect the Main Fuse(s):
* Locate the main fuses: Your Acura Integra's fuse box (likely under the hood and/or inside the cabin) should have high-amperage fuses that protect the main power circuits. Check these fuses for any blown elements. Replace any blown fuses with the correct amperage rating.
4. Check the Ignition Switch:
* Power at Ignition Switch: With the key in the "ON" position, use a multimeter to check for power at the ignition switch itself. If there's no power there, the problem could be in the switch or wiring leading to it.
* Ignition Switch Function: The ignition switch might be faulty and not completing the circuit, even if power is getting *to* it.
5. Investigate the Power Distribution System:
* Main Power Wiring: The main power wire from the battery to the rest of the system may have a break or loose connection somewhere. Trace this wire from the battery and check all connection points carefully.
* Wiring Harness: A damaged or corroded wire in the main harness could interrupt power to the fuel pump and instrument panel. This is more difficult to diagnose and might require a professional's help.
6. Consider the ECU (Engine Control Unit):
* ECU Power: While less likely given your symptoms, a problem with the ECU could prevent it from sending the signal to activate the fuel pump. However, this typically involves more than just lack of power to the fuel pump and instrument panel.
7. Professional Help:
If you've checked all the above and still haven't found the problem, it's best to take your Integra to a qualified mechanic. They have the tools and experience to diagnose more complex electrical issues.
Important Safety Note: Always disconnect the negative battery cable before working on the car's electrical system to prevent accidental shorts or injury. If you're not comfortable working with car electrical systems, seek professional help.
