I have changed the 02 sensor. Cruise will work when check engine light is reset but it surges and eventually check engine light comes on again. Outback is same.

Oh yeah. Any ideas on what is up?

Have you gotten the code yet? Advance Auto, Auto Zone etc. will check your codes for free. Get the code and then you'll have a better idea of where to go.

No subaru dealer here. Service is poor and knowledge is poorer. Will keep shopping for a knowledgeable mechanic..Thanks for your input.

All else fails, order a cheap OBDII scanner and get the codes that way. You're taking shots in the dark trying to diagnose a check engine light without knowing what code is being picked up. It's the whole reason the check engine light and diagnostics exist in the first place.