Was driving today and the engine lost alot of power to accel but kept the normal idle. Check engine light was not on. While i was driving, i turned the key off and back on(its a 5sp), all the power and snappiness returns. This has happened before in different driving conditions and weather conditions also but very rarely.

What can cause the ECM to go into limp mode with no check engine light?
I heard MAP sensor in some other thread.

 

That is odd. According to your sig, you don't have a chip, so that rules that out. Do you have a way to check for codes? Sometimes a CEL will not illuminate but the PCM will still have a code.

 

I dont have AE or the terminator gauge. I know the ECM was flashed so I have OBD2 but I dont know if the PO used a programmer or if its stock programmed.