Judicial Review Improvement Act of 1985 - Amends the Administrative Procedure Act to direct a court reviewing an agency action to: (1) set aside an agency rule the asserted or necessary factual basis of which is found to be without substantial support in the rulemaking file; (2) determine whether the action is within the scope of agency jurisdiction or authority on the basis of the language of the authorizing statute or, in the event of ambiguity, other ascertainable legislative intent; and (3) not accord any presumption in favor of or against agency action in determining any other questions of law.