Preparation for this work requires special tools, so be sure to read this entire technique and acquire these tools before starting. For the correct valve timing, the engines incorporate three timing chains of which the main timing chain the crankshaft and pistons together with the idler gear while the two other secondary timing chains attached on the camshaft sprockets. First, get the piston number 1 cylinder at the top of the compression stroke, then remove the negative terminal of the battery, and drain the cooling system, then the drive belt also remove the engine cooling fan and shroud. Disconnect the heater hoses and the lower radiator hose from the timing chain cover, remove the power steering pump without disconnecting the fluid, and the alternator, and the air conditioning compressor if fitted. The camshaft sprocket aligning requires the accessory drive belt tensioner, valve covers, spark plugs, and all the
Rocker Arms to be uninstalled to avoid piston striking of the valves. The camshaft position sensor is located high on the driver side valve cover and can be simply unbolted and removed, the piston number one has be at TDC on the exhaust stroke, the crankshaft damper/pulley, timing chain cover and water pump assembly will need to be removed. Put shop rags over the oil pan opening; retract the primary timing chain tensioner; and disconnect both secondary timing chain tensioners. To do this, you have to unscrew the camshaft sprocket retaining bolts, then take off the camshaft sprockets though you have to hold the camshafts as they turn. Loosen and take off the idler sprocket bolt and along with the idler sprocket, crankshaft sprocket and timing chains as a combine unit. Camshaft and crankshaft sprockets should also be checked for wear, the chains should be checked for cracks and tensioner components should be checked for signs of wear and major portions replaced. While installing the part make sure that the timing chain guides and the tensioner arms are fitted properly and the primary and secondary timing chain tensioners are fixed properly. Slide and fit the timing chains and the links correctly in place with the help of the idler sprocket, and fit the sprockets properly to the camshaft hubs. After the bolts have been removed and before reinstalling them, wash them and grease them as well, ensure that all the links of the timing chain are in order, and manually turn the engine in order to align the timing marks. Last but not the least, replace the timing chain cover and make sure that all parts are properly fixed; the engine oil and the cooling system should be replaced.