Hey all, newbie here - been a member for a while but haven't had anything of interest to say, however I do have a big problem with my S31 Fairlady which I can't sort out, hoping someone here can help me........

To save me typing it all out again, here's links to what's been tried so far (courtesy of www.datsun.co.nz):

http://datsun.co.nz/phpBB/viewtopic.php?t=1853

http://datsun.co.nz/phpBB/viewtopic.php?t=1907&start=0

And the latest:

http://datsun.co.nz/phpBB/viewtopic.php?t=2430

I wasn't sure which category to put this in, so hopefully this will find the right person.....

From what I read, plus what I've experienced on US EFI cars, I would check the connection to the temperature sensor as well as the temperature sensor itself. You stated that you 'fiddled' with the wires on the thermostat housing. One of those is the temperature sensor. The only other thing that could case richness when the engine is warm is a problem in the cold start circuit. Either a leaking cold start valve or a thermotime switch that doesn't shut down after cranking the starter. But when I had similar problem, it turned out to be a bad temperature sensor connector. I'm just not sure if the NZ cars are set up the same as the US cars but the should be some similarity.

Yeah, have checked all sensors and connections, but I'm positive it's not any of that. I'm thinking it's the 3v at the key that's causing the problems, as the sensors aren't getting the right voltage, so they can't supply the ECU with the correct signal.

For what it's worth, the ECU wiring on this car (from factory) is the same as the 280z you got over there, so I assume the rest of the wiring would be pretty close to the same.