Stalling

I have a EG9 , with a B16A2 engine . I did not use it for 1 or 2 weeks and yesterday as I drove it , from the begining I felt that something was not right . As I drove it , it felt to me that the car did not have it's full power . I drove it today , again and at approx. 4000RPM it seems that it is stalling like a fuel or spark cut . Also once I engage the VTEC at approx. 7000 it does the same . I hear the VTEC engaging , but it feels sometimes like I loose power ....