Vehicle Compatibility Information For Chevrolet Trailblazer 4.2L 2008-2009 For GMC Envoy 4.2L 2008-2009 For Isuzu Ascender 4.2L 2008 For Saab 9-7x 4.2L 2008-2009 Symptoms That Indicate You Need A Throttle Body Replacement Vacuum leak Poor or high idle Replace throttle body The throttle body is the part of the engine that mixes air with the fuel to allow combustion to take place. There are a number of symptoms that are often due to a failure in this part, including repeated stalling for no reason, problems with responsiveness of the acceleration pedal and stumbling or hesitation whilst accelerating. 1. Remove the Hose from the Throttle Body .
