I need some ideas...

[280z1975]

Clean connections on:

All six injectors

cold-start

aux. air regulator

thermotime switch

temp sensor

throttle pos. sensor

afm connectors

... and that's all I can remember doing ATM.

Also, seems like a lot less smoking now that I've dialed the AFM lean... which makes sense I suppose.

If your connections seemed really bad before you cleaned them you might want to replace, not just clean, the connection heads as the rust can ruine the wire inside.

There is an idle controle switch on the EFI cars, mostly for the cars with AC. It's so that when the AC goes on it will idle faster and create more power, maybe this is the source.

There might also be a problem with the cold start valve which adds more fuel to the mix when you start the car. You can disconnect it from the car and see if the car runs any better. The valve is only supposed to work for 12 seconds and then turn off, but it could be bad.

The EFI system is really realiable till something goes wrong, then it's just a pain in the a$$ compared to the carborator system which is much easier to trouble shoot, but can at times be unrealiable with some set ups.

[Roujin]

I would agree that your seals may be the problem. If you are going to go to the expense of new seals you may want to consider stainless steel seals. They dont crack and last virtually forever, best if you want to use LPG instead of petrol.