Hey,
Sure here is the description and instructions on the back of the can.
Subaru Upper Engine Cleaner contains a powerful foaming agent to efficiently clean the induction system and combustion chamber of the engine:
* Helps remove gum, varnish and carbon deposits from the combustion and intake systems
* Helps smooth rough idle
* Helps remove hot spots and marginal increases in compression ration which results in pinging
* Helps reduce pollution and improves fuel consumption
* Helps improve performance
Directions.
1) Warm the engine to normal operating temperature
2) With ignition turned off, remove convenient vacuum hose from intake manifold and spray approximately half the can into the manifold using the nozzle tube supplied with this can.
3) Allow the engine to stand for 5 minutes
4) Start the engine and run fast enough to prevent stalling while spraying the remainder of the can into the manifold
5) Stop the engine as the can empties and allow to stand for 5 to 10 minutes
6) Restart engine and rev engine to purge any remaining foam
7) Reinstall the vacuum hose

Road test the vehicle to ensure good performance
9) Extremely dirty systems may require reapplication