MX5Ireland

Hi
A friend of mine bought 02 mk2.5 1.8 vvt with only 45k that was parked up for nearly 2 years .
Starting no problem but it is idling high and if you bring it up off idle it starts to hunt up and down . It drove with no problems into storage seemingly but when previous owner went to bring it out of storage this problem happened .
So far replaced by previous owner was air flow meter and throttle body . theres a trouble code that refers to idle speed lower than expected
any ideas much appreciated ??

leak in the intake between air flow meter and engine? Missing rubber bung on one of the ports on the intake manifold? Idle air control valve a bit stuck?

this article also worth a read : https://miata.net/garage/isc.html