Chipping a Honda OBD2 ECU, or replacing the stock Memory Control Unit (MCU) with a reprogrammed one, is possible for models from 1996 to 2001. This guide provides a step-by-step approach to installing a racing MCU in these Honda ECUs. This modification can potentially enhance performance but may impact emissions compliance.
Locating and Removing the Stock MCU
The first step involves opening the ECU’s top panel. The stock MCU, an 84-pin PLCC square chip marked “Oki 66507,” is typically located in the lower left corner of the component side, away from the ECU plug. It’s easily identifiable as the largest chip on the board.
Next, carefully desolder the stock MCU. Use a fine-tipped soldering iron and a solder pump. Apply heat to each pin individually, avoiding overheating, which could damage the chip. Grounded pins might require more heat.
Once desoldered, the stock MCU should be removed, leaving behind the connection points on the board.
Installing the New Chip
An 84-pin PLCC IC socket needs to be soldered in place of the removed MCU. Ensure a secure connection and use a multimeter to check for any shorts between pins. Clean the area with a solvent like thinner or methanol to remove any residue.
The new, reprogrammed MCU (or the original if you’re reverting) can now be inserted into the socket. Ensure proper orientation before installation.
Final Steps and Verification
After installing the chip, reassemble the ECU by replacing the top and bottom covers. Reconnect the ECU to the car and the positive battery terminal. Start the engine to verify the modification. A successful chip installation is indicated by the absence of check engine lights and the ability to rev the engine past 4000 RPM. However, keep in mind that this modification might not comply with emissions regulations.
This process requires careful execution and a good understanding of electronics and soldering. If you’re not comfortable performing this modification yourself, consult a qualified automotive technician. Remember, altering your ECU could void your vehicle’s warranty.
