caprice P0606 engine control module

Hello every one
I have carpice 2007 6V
the PCM set code p0606 in one condition
just when the rps gets more than 4000 rpm
I did clean the throttle body and replace spark plug
the rpm gets more (5500)
but the problem still there
when the rpm get about 5500
appear to me on message center
( low engine performance ) (safety mode )
as soon as I get this message I scan for DTC and I found P0606


any one have any idea about this code ?
do I need to replace ECM ?
or what do I have to do ?
thanks

P0606: Control Module Internal Performance
I don't have any service info for that car, but I think the only course of action is to check the powers and grounds to the computer.
If it's setting at 4000 RPM, check the powers and grounds at 4000 RPM and see if something is dropping out.
If that checks good, then I believe the only thing left to do is replace the computer.

Yeah, these internal module codes are always tricky I'm with Noah, monitoring powers and grounds above 4000 RPM is the way to go.

Curious that the code only sets above a certain engine speed, and that the maximum engine speed changed with the throttle cleaning... I know this thing isn't setting 5V reference circuit codes, but it may be worth monitoring them on a scope while the code sets.

Thank you very much
I appreciate what you are say

No problem! Let us know where this one ends up, if you get the opportunity