986 CEL on after storage

[Rundtinden]

The car has done 130 000 km.
Stock air filter.
Mods: Plenum is from Pedro with a splitter in it. Throttlebody from an early 996. Stainless steel exhaust and headers. Underdrive pulley. This configuration worked fine until I put it away for two years.
Has changed the plugs, inspected the coils, changed oil, filter and air filter. New waterpump and coolant. Changed a sleeve with a hole in it. Has checked twice with start gas, cannot find any more vaacum leaks.
It was stored with very little fuel in it. Have not changed the fuel filter yet.
Will try clean the MAF and change the filter tomorrow.
The car now idles at around 900 rpm. Up and down maybe 100. When I have driven for a bit the idle seems to rise to about 1200. Then settle down again if I hit the throttle for a second.
At 2500 rpm and above I cannot detect any misfires. With light throttle and below 2500 I can hear and feel less than smooth operation from the engine.
With full throttle it picks up speed fast without any detectable misfires.