[Unknown User]

I have an 81 280zx - all stock. It starts fine warm or cold, and idles fairly evenly (slow oscillation between 700 & 800 rpm), but during warmup, the idle speed drops from 750 rpm to 500 rpm, and there is noticeable hesitation when accelerating (I keep the revs below ~ 3000 rpm until warm anyway).

Any ideas what could be causing this problem?

Thanks,

Darryl

 

[Unknown User]

> I have an 81 280zx - all stock. It starts
> fine warm or cold, and idles fairly evenly
> (slow oscillation between 700 & 800
> rpm), but during warmup, the idle speed
> drops from 750 rpm to 500 rpm, and there is
> noticeable hesitation when accelerating (I
> keep the revs below ~ 3000 rpm until warm
> anyway).

> Any ideas what could be causing this
> problem?

> Thanks,

> Darryl
If it smells over rich when cold, check your air regulator and make sure it's open when cold,other thing to check is your cold start valve and make sure it works, haynes has the test proceedure for both in the book.
happy motoring!