On the 1.4L engine, start with the detaching of the cable of the negative terminal of the battery followed by the removal of the engine cover. Remove the outlet pipe from the charge air cooler and disconnect any wiring connections that may hinder the removal of the manifold, then open all the clips that are on the wiring harness and separate all the wiring harnesses from the manifold. Remove any vacuum hoses connected to the manifold particularly that connected to the brake booster if the car has a vacuum assisted brake system and give these hoses and identification if necessary for proper reassembly. The fuel pressure must be removed and the hose of the PCV from the intake manifold and fuel feed line from the fuel rail must be removed. You can take off the vent line from the EVAP canister purge solenoid valve, and the intake manifold mounting bolts to free the intake manifold, then loosen the bolts, then unclamp the intake manifold away from the 
Cylinder Head. For installation, fit a new gasket to the manifold, the mating surfaces of the manifold and cylinder head must be clean. Position the manifold against the cylinder head while loosening the nuts of the bolts, immediately and successively tighten them to the required torque beginning with the middle bolts and later the outermost ones. The rest of the installation is performed in the reverse order to removal then reconnect the battery and take the engine through its tests for vacuum and fuel leaks. To do the modifications for the 1.8L engine, one has to first unplug the cable from the negative terminal of the battery and release pressure in the fuel system. Take out first the air intake duct and the throttle body; unbolt the fuel rail and the fuel injectors; any connectors which may hinder the removal of the manifold should be disconnected by opening the wiring harness clips and detaching all wiring harnesses from the manifold. Remove any vacuum hoses connected to the manifold, the one to the brake booster, if used, and note them for reconnection. THE FOLLOWING STEPS INCLUDE: Disconnect PCV hose from valve cover, remove the intake manifold brace if installed beneath the intake manifold and then remove the intake manifold bolts the holds the intake manifold to cylinder head After removing all the above parts, then remove the intake manifold from the cylinder head. For installation, new gaskets are best fitted to the manifolds with the mating surface of the manifolds and cylinder heads in place. Position the manifold on the cylinder head and fit the bolts loosely, then tighten them to the recommended rating round the central bolts to the outermost ones. The rest of the installation is the exact opposite of the removal procedure, reconnect the battery last, after that engage the engine and check for any vacuum and fuel leaks.