An on-again-off-again car chase, lasting a couple hours, ends in Janesville.  Authorities say the pursuit went through several counties before ending about 11:30 p.m. Wednesday near the intersection of Sherman Avenue and Parker Drive.  Law enforcement agencies from several jurisdictions participated at one point or another in the chase.  Rock County Sheriff’s deputies eventually made the arrests of five suspects.  The vehicle was determined to have been stolen from the Chicago area.