Does the the legacy have a safe mode? as my Legacy keeps loosing power, it starts to miss a bit for about 2-3 secs and then looses all boost and when it feels like it you get the boost back

I have checked the check light and it records nothing

can anyone suggest anything????

 

It does have a safe mode, just as the impreza, but it does not necessarily cause a CEL, or register a fault code.
The only time I seen this happen on my car ( some time ago, before losing the std boost control ) was when the chargecooler pump was not working. I dont know what actually triggered the low boost, as the ecu does not measure air temp, and I certainly never heard any det. I re-wired the pump ( the original wiring had never worked for some reason?? ) and things were fine again.
The symptoms were as you describe. Driving normal , then suddenly low boost, for a totally random period of time. Eventually the boost would return.