Idling problems with a JDM 12AT engine

[Traxnada]

Hello guys!
So, I recently replaced the trailing ignition control unit on my JDM '85 12a Turbo (EFI). Now the car works like it used to and I'm VERY happy with the results!
I still have a little problem with idling though. I would have thought changing the ICU would fix the problem, but nope...
Description: When cold, the idling makes me think a bit of a cammed V8 engine. It has some kind of a weird rhythm to it that has nothing to do with a rotary. Once the engine gets a bit warm, idling stabilizes itself but way too high, around 1300rpm. If I give it a bit of throttle (up to 3500-4000rpm) then let the RPM fall down to idling, it will stabilizes around 700rpm (a bit too low), but just merely touching the throttle, sends it back to 1300/1400rpm right away.
If I shut down the car for a couple of minutes, then turn it back on, the idling will be CammedV8-ish for 30s, then stabilize again at 1300-1400rpm.

Other than that, everything is great with the car. No problem at all, great throttle response and tons of fun. It's just this idling problem that is a bit annoying since my car is daily driven.

If anyone has an idea as to what might be wrong, I'm all ears

Thanks,

Flavien

[Hobbawobba]

I don't have a clue what the problem would be. But maybe uploading a video on Youtube might help a bit?

[Traxnada]

I don't have a clue what the problem would be. But maybe uploading a video on Youtube might help a bit?

OK I'll do that tomorrow then
11pm here already so...

[KiwiDave]

Sticking throttle cable or throttle body?

[myatt1972]

Sticking throttle cable or throttle body?

My first thought to Dave.

[KiwiDave]

Sticking throttle cable or throttle body?

My first thought to Dave.

[Traxnada]

So I just came back from the car... Of course, because I was trying to shoot a video it hasn't caused as much problem as usual
Nonetheless, you can hear what I mean by weird CammedV8-ish idling at 4min40 and 6min05 in the video.
I will look for a slightly stucked throttle cable, but I doubt it is the problem... Could be nonetheless so I'll WD40 the shit out of the cable, we'll see

[Hobbawobba]

Oh that does seem quite strange (to me at least). Wouldn't a stuck cable would keep it at the same RPM rather than fluctuating? Love the car by the way!

[Traxnada]

Oh that does seem quite strange (to me at least). Wouldn't a stuck cable would keep it at the same RPM rather than fluctuating? Love the car by the way!

Yeah, I doubt that's the problem either... To make it jump back from 700 to 1300rpm, I also merely have to touch the pedal, not even really pressing it. Not pressing it enough to make to gain 600rpm anyway...
And thanks

[DB RX63]

Check all of the ignition components, plug leads, coils, distributor cap and rotor etc. Often these things can be electrical when they seem mechanical.