Eric, perhaps (as stated above) this was a repaired ECU and all might be just fine. Only way to know is to give her a try. Make sure the NiCads are charged. Hook everything up and turn it on. You should see a temperature reading. Take a lighter and put a flame under the end of the thermocouple (at the exhaust nozzle of the RAM) and you should see an immediate temp rise. If this happens, chances are the thermocouple is just fine. Spin up the engine briefly with some compressed air and you should see the pressure reading on the display show an increase. Problem for me is that it has been too many years since I owned a 750F that I am starting to forget if these readings are always displayed or if they only display after a start is initiated.

Another problem with the older Electrodynamics ECU was that interface plug (that you plug the ground display unit into). Either where the wires go into the plug or the socket (can’t remember which, getting old here!), there was a batch of bad ones made. They soon became intermittent and sometimes you need to wiggle the connector until you get a valid display. I had one that you only had to wiggle it a little and it would function just fine. But then I had another that would get worse and worse until it was hopeless. I found the same connector on an Mac keyboard or something that was being thrown out so I scavenged it and soldered it in for a fix. So if you get no reading or funny stuff, try wiggling (not you, the connector!).

If you have problems, give me another call, you got the number!