I have owned my 1978 280z for about 20 years. It was the most reliable car I have ever owned. About a year ago it would just turn off while I was driving it.  I have replaced the following:

New stock pump pump

had the fuel tank drained-it wasn't bad

new fuel filter

new relays under the black metal cover in front of the battery

new relay behind the glove box (I can't remember the name of it)

New computer from Z man in Washington

I have ordered a new air control unit

After deciding what was wrong with it was beyond  me I took it to a local foreign car repair place in town. They got the car to run better by replacing the computer. They said they could tap the top of the old computer and the car would just die. The new one solved that issue. They drove it a couple of times and it would still act up occasionally.  I drove it for a week and it died and stranded me. I had it towed back to the shop, They worked on it cleaning some connections. I went and drove it home. Two weeks later I started it and it would not produce than than about 800 rpms. It will not accelerate at all and smokes a good bit. It acts like it is very rich.  I down loaded the 280Z Fuel injection bible. I have ordered new temperature probe and new plugs that are located where the top radiator hose attaches. 

I am getting sort of frustrated with it.  Any suggestions will be appreciated. Can anyone recommend a central Florida repair place with Z experience? I live in Vero Beach.

Thanks

Curt

I can live with it idling like it does. M biggest problem is lack of confidence that I will make it back to the garage. The last two trips ended up with a wrecker. Why does it run well for a while and then either stalls, stops or runs terribly and smokes a lot ? I think there could be an electrical component that breaks down with load or heat. The fuel tank is fine. Installed a new stock fuel pump and filter. I bought a new ICU, all new relays, cleaned the grounds. I am very open to suggestions or ideas. I brought it to a local sports car shop. They have a very good reputation but if the tech can't hook a computer to it they don't know where to turn. Thank you for your post.

Curt

1 hour ago, siteunseen said:

After reading more it sounds like you're onto something electrical related? I was just thinking of some easy things to check first. Here's the AAR plug-in and one of the best helps I've gotten for my '77 280. Good reading with lots of photos. Hope you get it figured out soon.

http://atlanticz.ca/zclub/techtips/aar/index.html

http://atlanticz.ca/zclub/techtips/EFI&fuel.htm

http://atlanticz.ca/zclub/techtips/

Thank you for all the helpful info I really appreciate it. Looks like I've got a lot of reading to do. I will post the results.