Im having trouble with my stock 77 280z. I tried to start it the other day and it wouldn't fire. After some investigating found that it was flooding, badly. This problem came out of nowhere. I've seen some posts around saying that an ECU or Air flow meter could cause this but I thought i'd see what you guys think the problem is.

Please Help

Leaking cold start valve, bad thermotime switch, fuel pressure regulator, leaky injector(s), are things I'd check before proceeding to the ECU or AFM.

I agree with Stephen. Check the items that are made to wear out and be replaced and replace them. Odds are that if they are not the originals, they are old replacements and would be due for a freshening.

Additionally, check all of your connectors, both electrical and fuel related.

check battery also. thats what happen to mine.

Thanks guys I believe that I traced it to the fuel pressure regulator but it still isnt quite running like it did. Im sure new injectors couldnt hurt anything.

Thanks again

Old thread new problem. Rebuilt bottom end, I'm not sure what is wrong with the car, its either getting flooded with gas or starved. The car will start then after a while it will die. Replaced the temp sender and thermotime switch. Also dropped the gas tank and cleaned it out along with installing a new fuel filter. I have no leaks in the system and when I take the plugs out it doesn't smell like gas as it would if it was flooding. Any other ideas?

The cold start valve doesn't seem to be working either. The only way it seems to get the car started is to bridge the Cold Start Valve to the battery like you would if you were de-pressurizing the system. Could the problem be in the ECU? Help?

How's the fuel pump and pump relay?

Just fine as far as I know. I'm not quite sure how to test them though.

well the pump SHOULD kick in after you crank it for a bit (on my 78 the oil pressure sender kicks it on)

what i did to figure out what was wrong, was i pulled off the tps plug, and the cold start valve. my car's still running really rich, but it runs ok. In my case, it's VERY corroded water temp sensor plugs (the bullets are a bit corroded too)

any corrosion on those will cause the car to run horribly rich. and the tps will cause it to run even more rich, since the tps make it run RICHER (basically) i unplug the cold start valve to make sure it isn't on while i'm checking things.

Is it a problem that my fuel pump is on when I turn the key into the on possession? I'm not sure but it has done that ever sense I got it. I've replaced the temp sending unit and the thermo-time switch. Is there anything else I can do? How would I get my fuel pump to only come on when I crank then engine?

Yeah, I hear mine running on "77 when turn the key into

the on position too.

Humming sound when I want to listiening to the radio :cheeky:

if it comes one when you turn it to the on position it means your relay is bypassed. the wires are under the passenger carpet behind the seat, but they may be bypassing it at the other end (don't knwo where it goes)

take a look at a wiring diagram and you'll figure it out ^^ on the 77 i think the afm kicks the pump on. on the 78 the oil pressure sender does.