What does Code "3000 rpm" mean ?

[thyrsted@olsy.dk (Kenn Thyrsted Nielsen)]

Hi.
I'm experiencing an periodic problem:
Recently the engine check light is coming on under light to medium acceleration.
(also under full throttle, but i only checked this once)
Slightly backing off the throttle makes the light dissapear, and i can feel the engine pulling more willingly (not much).

I pulled the codes; it said 3000rpm (MAC 06A).

Could it be the knock sensor ?

TIA
    Kenn '87 200TQA