I have a 1977 Datsun 280z, since i bought the car it ran good but once in a while it runs rich and starts to flood out. When i give it gas it starts to sputter.I been trying to find this problem for a while now and i cant figure it out. People tell me its the water temp. sensor, i changed it and it still does it. It seems like the problem will go away for like a week but then it comes back, I'm thinking it could be a relay, but i don't know what it is, Can someone please help me! Thank You.

Edited March 15, 200916 yr by nissan280z

There's been a number of posts on this issue. Many things could cause this. Leaking injector, leaking cold start valve, bad thermotime switch which would cause the cold start valve to work when it shouldn't, bad throttle valve switch, water temp sensor as you mentioned, fuel pressure regulator, bad connections at any of the above mentioned items. Do you have a factory service manual? It has step by step troubleshooting instructions.

i just changed all the fuel injectors,fuel pressure regulator,fuel filters watertemp senor...i even ran it with the cold start vulve unpluged!! but it steel does it...

In all of this work switching parts out, did you take the time to clean thoroughly all the connectors? What condition are your pigtail connectors? How about the connectors that go to the thermotine, water temp sensor, etc...? Can you just push them on and pull them off easily? If so, you probably have crud or looseness in there that causes bad connections.

Think about it: You fiddle with things (and end up getting a good connection) and the car runs. After running for a while, the connections loosen up, and you are back to having the same problem.

It's not hard, nor does it take much time to go and check them and clean them out really well.

If nothing else, doing this will help shorten the list of possible causes.

i put alot of time into my car ive cleaned the connectors to......but when it starts to sputter and running rich i pull the spark plug wire that goes to the coil to see the spark! wheal it steel running ! it clears up. and i even bot a new coil. and distributor to!! i practically changed everything.