How to install a Chip on 96-up OBD-II Honda ECU

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Here is a step by step guide toward installing a racing MCU on 1996 to 2001 Honda OBD-II ECUs. First, open up your ECU top cover.

Figure 1
Engine Computer

Figure 2
Remove Top Cover

Open the top panel of the ECU. Figure 2 is a view of the ECU Components side. Look for the Stock MCU a 84 pins PLCC square chip with the marking Oki 66507. It is at the lower left corner away from the ECU Plug (top view). Quite easy to spot as the biggest chip in the ECU.
Desolder the stock MCU Figure 3 Use a niddle point soldering aid like CHIPQUIK touching the base of the pin. Do not overheat the Stock MCU, that will distroy it. Hold the solder pump close to the heated pin to pump up the solder. Be careful on the grounded pin or pin 1 as they are tougher to desolder.

Figure 3
Solder side of the ECU

Removed the Stock MCU. Figure 4 show the stock MCU chip after being removed.The 84 pin PLCC IC socket is going to be soldered on the same spot where the stock MCU use to be.Figure 5 show the spot where stock MCU used to be after being desoldered.

Figure 4
The removed Stock MCU

Figure 5
The Stock MCU Location after desoldered

Install the 84 pin PLCC IC Socket. Figure 6 shows a 84 pin PLCC IC socket installed in the removed MCU position. Solder it in place and use multimeter to check any short on the pins. Figure 11 Clean up the soldered area with solvent like thinner or methenol to remove any residue near the pins.

Figure 6
PLCC IC socket install in stock MCU position

Figure 7
Newly reprogrammed MCU ready to be installed

Figure 8
Install chip unto the IC socket

Insert the New Chip or the old stock MCU in the socket. Figure 8 showing the Racing MCU is being installed unto the IC socket. After that, just reinstall the ECU top and bottom covers. Plug the ECU back on the car, reconnect back the battery positive terminal and start the car to check whether the car is runing fine.If you don't any check light and able to rev pass 4000rpm, you have just successfully chip your ECU.