The dash is powered and the signals come through the harness. Next to the ECU there are some other connectors (white and grey i think, about 20 pins in each) - most of the connections run through that. Do the dash lights work, like the battery light etc when you first key-on?
Did you ever have any misfiring problems at idle? Ive had the car running from cold a couple of times while tuning the warmup enrichments and idle fuel cells, and its all good until she warms up, then i get misfires like crazy sometimes until it dies. Other times it will catch itself and come good. I have EGO correction off and pulse widths dont change at all, but I can hear the misfires and the wideband reads from ~14 all the way up to 17-20. I have tried all different req_fuel values both lean and rich to no avail. I first thought it could be the ignition signal, so i cleaned the points and ran my own shielded tach signal and earth from the dizzy. This didnt seem to make any difference. I'm having trouble understanding why it only happens when its warmed up, and why its not consistent (sometimes dies, other times it picks up again). Any ideas?
Watch your inlet temp sensor - when sitting still you may be getting heatsoak of the sensor depending on what sort of sensor you have and where its fitted. It starts reading really really hot air and leans out to match it, but in fact the air temp hasnt really changed /that/ much, just the sensor. I had this at first but I more or less eliminated it by: Removing the heater/coolant feed to the throttle body (big difference) Making sure the IAT sensor had no extra metal around the sensor head itself - it was a caged sensor so i chopped the cage off. There is CLT based correction on the MS-Extra code - watch the point in the logs where it starts to go lean and watch the maximum temperature the engine reaches while idling and make yourself a CLT-fuelling map - this just adds extra fuel to match the raising CLT values. Its not an exact science as, obviously, the IAT is not exactly related to CLT but it helps if you still cant cure it with the other methods above.
