Procedure
When motorists enter the test facility, they hand the inspector the registration renewal notice. The inspector enters essential information into a computer that automatically selects the proper test-type and standards for the vehicle's weight and model year. Most model year 1996 and newer vehicles equipped with On Board Diagnostic II (OBDII) computer systems are tested by means of a computer "health-check". This check consists of plugging into the vehicle's computer and downloading emission system information. On other vehicles the tailpipe emissions are measured while the vehicle is driven on a treadmill-like device called a dynamometer. The vehicle is operated over a driving cycle that simulates typical city driving and includes periods of acceleration, cruise and deceleration. After the OBD check or emission test, the vehicle's gas cap is tested to ensure that it seals properly.
This applies to new registrations too. Considering your is older than 1996 I don't know for sure if they will do the OBD test.