Where exactly is the cam shaft timing mark for 1 point 8 liter valve engine?

There is no cam shaft timing mark for 1.8-liter valve engines. Instead, the camshaft position sensor (CMP) is used to determine the position of the camshaft. The CMP is located on the front of the engine, near the top of the cylinder head. It consists of a magnetic sensor that reads the teeth on the camshaft reluctor wheel. The reluctor wheel is attached to the camshaft and has a series of evenly spaced teeth. As the camshaft rotates, the teeth pass by the sensor, generating a signal that is used by the engine control unit (ECU) to determine the position of the camshaft.