[Jake Raby]

Way low.. My guess is this shop wasn't keen enough to do the compression test with the throttle locked open.. The throttle plate being partially open in the idle position effects chamber filling nd seriously effects the compression test.

Any healthy Boxster S will produce over 200 PSI on a compression tester, even here at 1765', as long as the throttle plate is locked open. 150# is very low with the throttle plate open, if it was.

Its pretty simple, air that isn't inducted can't be compressed, so the readings are always low with a closed throttle plate and they are also impacted by intake system characteristics more. Ask them how they performed the test.