Installation Warnings

Top  Previous  Next

Hondata's warranty will not cover damage to the ECU and/or FlashPro from the use of low impedance injectors, non-resistor spark plugs and/or incorrect engine ground location.


Injector Impedance

The Honda ECU is designed to use high impedance (or 'saturated') injectors. The use of low impedance (or 'peak and hold') injectors will damage the ECU and/or vehicle wiring. Low impedance injectors can be used with the addition of a resistor box, but it is recommended to use high impedance injectors if at all possible.


Non-Resistor Spark Plugs

Do not use non-resistor spark plugs. Non-resistor spark plugs cause a large amount of electrical interference which may affect vehicle electronics, including the ECU.


Engine Ground

It is very important that the ground from the wiring harness to the engine (G101) makes good electrical contact with the cylinder head.  Otherwise the return path for the sensors, ignition and VTEC may be through the OBDII connector, FlashPro, laptop, laptop charger and inverter to the vehicle body, which may damage the ECU/FlashPro.



The recommended position for the engine ground is on the stud attached to the cylinder head. While the stock location on the intake manifold will usually work without problems, the stud on the cylinder head provides a better electrical connection. The top bolt holding the radiator water output to the cylinder head is also a good alternative for the ground wire.



Software Versions

Do not 'roll back' or 'backdate' software versions.  The reason for this is that the FlashPro firmware will be updated by the newer version of software, and an earlier version of software accessing a FlashPro with a more recent firmware version may cause the FlashPro to not function correctly.


Reflashed ECU

If you ECU has been reflashed by a company other than Hondata do not use the FlashPro until the ECU has been reflashed back to stock by the original company.  The reason is that most reflashed corrupt the ECU flash memory, so that they cannot be reflashed again.