Q: How to replace the Idle Control Valve on GMC Jimmy?
A: Before starting Idle Control Valve replacement start by removing the negative Battery Cable and iat sensor harness connector. Next, detach the breather tube from the air cleaner outlet duct keeping in mind the wing nut securing the duct. Finally, loosen the maf sensor outlet clamp to remove the Throttle Body until the Idle Control Valve and o-ring seal. First disconnect the Idle Control Valve harness connector while undoing the maf sensor outlet clamp then lift the air cleaner outlet duct from the Throttle Body. Start by unhooking the Idle Control Valve mounting screws from the Throttle Body assembly to extract the Idle Control Valve along with its o-ring. Apply carburetor cleaner from a parts cleaning brush to the Idle Control Valve o-ring sealing surface and the pintle valve seat along with the air passage. Be careful not to submerge the Idle Control Valve in liquid cleaning solutions or solvents. Apply replacement Idle Control Valve o-ring before checking the pintle distance to its housing end, which should measure under 28 mm (1-1/8 in). Compress the pintle manually if distance from the valve motor housing to the end of the pintle exceeds 1-1/8 inch. After applying clean engine oil to the new Idle Control Valve o-ring you should insert the valve through the o-ring until all flange holes match the Throttle Body assembly. The Idle Control Valve mounting screws need clean screw threads before receiving application of thread locking compound gm p/n 1052624 or equivalent followed by screw torquing to 3 n.m (27 lb in). After attaching the Idle Control Valve harness you should reinstall the air cleaner outlet duct while tightening its wing nut and duct clamp to 4 n.m (35 lb in). Connect all components including the breather tube and the iat sensor connector as well as the negative Battery Cable before resetting the Idle Control Valve pintle position.