Vehicles up to MY '96 1/2: detach plug strip from injectors and disconnect wiring harness plug for knock sensor (1) from plug strip - see operation "Injectors, Remove and Install". Vehicles as of MY '96 1/2: disconnect wiring harness plug for knock sensor (2). Detach knock sensor (3) from cylinder block. Pull cable for knock sensor out downwards - note cable routing.
 Important! The entire contact surface of the knock sensor must lie directly on the cylinder block - ensure utmost cleanliness. Do not use washers, spring washers or toothed washers. Maintain tightening torque exactly. | 
Remove, Disconnect 
Install, Connect