Idle Issue
 

Hello my name Chris
When I start my car and it has been sitting for at least 2 hours for some reason it doesnt want to hold its idle so I have to hold in the gas until it warms up then it can hold itself.

A friend said it may be a bad air flow sensor and I read somewere else that it can be adjusted.

Another person said the EGR Valve is to blame.

Can anyone help me?

Welcome to ZDriver! :006:

What year car? Turbo or n/a?
How does it run after it's warm? Any other problems?

Have you checked the timing?
Sensors and connections?
Spark plugs, wires, cap, rotor?

Its an 82 non-turbo 2+2 280zx
After its warm it runs great! We just put a new head on it and swapped all the bolts over to studs.
New timing kit also. The timing was done when the motor was together again, wich was about 3 weeks ago.
New spark plugs, fuel injectors, and water pump too.
The only other problem with the car is that the radiator is messed up.
Like if you drive it for a long distance it will start to get hot.

Is the air flow sensor nessesary?
Can I remove it?
And what exactly does it do?
Sorry for so many questions at once.

Idk what your idle issue is, you didn't give enough details. but its probably your IAC sense they fail commonly

YES! Its VERY important. No AFM, car wont run.
No
Uh idk Measures the airflow into the engine so it keeps the air/fuel ratio correct.
Its ok every has questions

Whats the IAC?:102:

I think he meant the Air Regulator.

Also check the cold start valve to make sure it's spraying when cold.

prolly the air reg. i removed mine and it does the same thing, cold start injector hooked up or not. its not a big deal, but get that rad fix pronto, no need to overheat a perfectly good engine.

I always knew the IAC as the Idle Air Controller. oh well lol

I know what an IAC is, but does the 82 280zx have one?

Does the same thing, different name. lol So technically yes

So if the IAC is not the Air Regulator, where is it?

I said, its the same thing, different names. IAC=AIR REG visa versa

We think its the vaccum control valve. It has a hose that runs to the EGR valve And that hose isn't getting any air no matter how hot or cold the engine is. Does anyone know what the vaccum control valve does?

What does the air regulator look like?

Follow this link:

Service Manuals

Grab the manual for your year... once downloaded, look for the PDF that says "Engine Fuel"

no run cold run good hot often the chts. cheap and easy to replace. check the wiring to it for damage. might need a new connector.

my car has the same issue it a 82 non turbo. and when i was playing around with a air regulator when i unplug it noting changes with the idle. is that normal. or is it bad

I figgered it out, Sorry for some reason i thought it was called and air flow sensor.:017:

That might meen that that part is bad if you unplugged it and nothing changed.

ya i ordered a new one

So... what was it??

Oh my bad. I meant that I had figgured out what the air regulater was.
But we did order the vaccum control valve from nissan and I will post up what the result is. According to Tidewater Z, the symptoms that my car is having are caused by the bad valve wich they said was very common so were trying that first.

It wasnt the vaccum control valve though it did make it run less smelly.

So after the car warms up the idle gets much better and the after it runs for a while the car starts running like its got a turbo because at around 2500 you get a sudden burst of power that feels like your being pinned to the seats, what causes this?

I would say your Z is running a lot better. And everything is working properly. It should put you back in the seat. When it is running 100%. I know from experience. These N/A's alone, have quite a kick for stock. I can't imagine what a Turbo would feel like. I would probably get whiplash. lol

2500-4500 is your power band for a non turbo ZX...third gear is probably where you feel it most...second and fourth will be strong but third around 3500 is the "im haulin ass" gear.
Off the line the stock ZX doesn't have nearly the torque other cars have, but upwards of 45mph and on...hang on! I used to smoke all american cars once on the interstate from 60 mph up...but they would eat me up off the line...it is the gearing ratio.

The Imports of that time were almost all like that...Toy Supra is exactly the same way in the late 80's...all geared for high end speed.