Looking through the technical information, I think it may be that the EFI ECU isn't getting a valid signal from the temperature transmitter. I believe that the bi-metallic-strip temperature gauge has gone high resistance and that therefore the voltage across the sender is too low (this also means the gauge reads far too low). As far as I can see from the techie documentation, the EFI ECU also sees this same voltage signal. If it is too low, the ECU will think the engine temperature is too low. Does the instrument pack put out a regulated 10V for these gauges? In the old days these sort of gauges used 10V but I know that 7V was also used by some manufacturers. I didn't have a chance this last weekend to look into it, but I'm taking the week off work just before Stoneleigh weekend, so I'm hoping for good weather!
I intend to buy the latest K3 ECU from Dave Walker (Emerald) to replace the over-complicated Honda system. Using this will simplify the engine wiring considerably as it uses a direct-fire triple coil pack, although I'm not convinced of my ability to get the fuel and ignition mapping sorted out properly.
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