Ok i have a 1977 280z FI it will work one day and completly die the next. It wont even start with starting fluid. It has plenty of spark, fuel, air. I have no idea what to do help please.

You could start by using the search function. There has been a lot of discusion on 280 FI lately.

Can't help wondering if some of the componentry is reaching a used by date?

MOM

computer problems?

it might be the ECU because i have checked the water temp. sensor, water temp. switch, Thermotime switch. all vacum lines are new and in the right place. i pulled the spark plugs they are complety soaked in gas.

Or possibly the cold start valve (if it has one)

Could it be stuck open?

I don't know if you've checked this or not, but on my 75 I could start it up and drive it but if I turned it off anywhere it wouldn't start again. I also noticed that the plugs were soaked in fuel and after switching them out it would run. After driving around with 3 spare sets of plugs in the car for a while, the guys at Tidewater Z determined it was the Air Flow sensor. or I guess in our case its technically a vane air meter. But anyway hope this helps.

Have you run a fuel pressure check?

I havent checked fuel pressure but i did get it started, and it ran so bad i couldnt rev past 1500 RPMs and it filled my garage with blue smoke. It sounded like it was running on three cyinders. I unplugged the cold start valve (that wont hurt it. will it?) and it didnt do any thing. I would change ECUs but i dont know anybody around with a 280z. So i think i will spend a few more hours looking things over and what not

Ok last question. My fuel pump is on when the key is to the on position and the car is off. is it always pumping fuel or should it turn off after a couple of min. shouldnt there be a relay of some sort.

there is a fuel pump relay under driver dash, someone probably wired your pump hot to ignition. That is a common fix for these cars. If your plugs are fouling w/ carbon, look into AFM, it maybe choking car of air, making mixturetoo strong. Remove hose btween AFM and throttle valve, the car willstill run but it will sound lke a vacuum leak, if it runs better, buy yourself a new AFM, I am on #3 of these already. geo

usually the pump just builds up pressure for the next start up and i had the same problem with my z it just runs too lean i replaced the injectors vacuum lines and the air meter and it seems to run just fine now

my car did this one morning randomly, ran so rich, blowing smoke and no throttle response, just dying if it started, and it was so rich I was getting gas past my rings into my oil. I swapped engines because of it out of another z with a l28, but I've still had issues with mixture and crazy issues with hesitation, throttle response failure and basically running like a dog. I've checked nearly everything, and what boggles me is that it's bi-polar just like yours, one day it runs perfect, another day off the heezey messed up...

basically, I've noticed inthe last few days that if I play with the sweeper and the connections and grounds of my AFM, just making sure it's all making good contact, it runs fine. this is just an idea, but it's what has worked for me for the past 2 or 3 days so far.

so I'd say look in to the AFM and ALL it's connections, especially the sweeper, make sure it's contacting that strip well. might help =)

good luck