Q: How do you remove and install the timing chain and Sprocket in 3.8L V6 engine on Pontiac Grand Prix?
A: To remove the timing chain cover, slide the shim off the nose of the crankshaft, ensuring the shim's notch fits over the key in the crankshaft. Replace the timing chain if the total free play between the sprockets exceeds one inch to avoid erratic engine performance, loss of power, and reduced fuel mileage. Temporarily install the vibration damper bolt and turn the crankshaft clockwise to align the timing marks on the crankshaft and camshaft sprockets directly opposite each other, with the camshaft sprocket marked by a dimple and the crankshaft sprocket by a raised dot. Remove the timing chain damper, detaching the spring on earlier models if necessary, and then remove the camshaft sprocket bolts, taking care not to turn the camshaft. Pull the camshaft sprocket and crankshaft sprocket forward alternately to remove them along with the timing chain as an assembly, followed by the camshaft gear. Clean the timing chain components with solvent and dry them with compressed air while wearing eye protection, then inspect for wear and damage, looking for deformed, chipped, pitted, polished, or discolored teeth. If the crankshaft has been disturbed, temporarily install the sprocket and turn the crankshaft until the mark on the crankshaft sprocket is at the top; if the camshaft was disturbed, do the same for the camshaft until its timing mark is at the bottom. Assemble the timing chain on the sprockets and slide the sprocket and chain assembly onto the shafts with the timing marks aligned, ensuring the balance shaft gears are also aligned before installing the camshaft timing chain sprocket. Install and tighten the camshaft sprocket bolt(s) to the specified torque, attach the timing chain damper assembly to the block, and install the spring. For 1994 and earlier models, install the camshaft thrust button and spring, securing it with grease. Lubricate the chain and sprocket with clean engine oil and install the timing chain cover, remembering to lubricate the oil pump cavity beforehand.