[Unknown User]

i have a 77 280z 4speed. when i start it cold, it idles real low(round 400-500rpms) and under very light throttle, sputters a bit. but after it warms, runs good and idles steady at 700-800. now i thought that with FI, it would automatically compensate for the fresh start? it really seems to be running on carbs without a choke! or maybe it's that cold start or thermotime switch i keep hearing about. never have even looked at where those things are on the motor.

 

[NathanZ]

I have same problem!

Only mine is intermittent. It will happen exactly as you said, and goes away after the engine warms up a bit. Vacuum leak? Bad connector(s)? It did happen for the first time after I cleaned the motor with water and I undoubtedly got some connectors wet..... hmmm.
Nathan

 

[yo2001]

Re: I have same problem!

MAY BE THE AIR REGULAR ISN'T OPENING UP

 

[NathanZ]

Noise coming from that area:

I have noticed that when my car is completely warmed up and idling, that the air regulator, or something near it, makes a buzzing sound and vibrates (if you touch it, you can even feel it). Just to make sure, the air regulator is the thing with a hose going to the valve cover, and a connector on it right? Is this vibe normal? And what does the air reguator do?
Nathan

 

[SleeperZ]

Re: Noise coming from that area:

The air regulator is open when the engine is cold, allowing more air past the throttle, and allows the idle to increase. Normally the engine should idle high when cold, and settle into a good idle when it worms up. The air regulator is where I would look first, if the car works normally when warm.

 

[NathanZ]

Thank you

I will be checking it soon!
Nathan