Engine

Overview of engine performance modification options for the 944 Turbo (951), covering computer chips, air flow measurement, fuel management systems, stand-alone engine management, turbochargers, fuel pressure regulators, injectors, engine displacement increases, boost control, oiling system improvements, and rotating mass reduction.

Procedure for replacing balance shaft front oil seals and resealing the balance shaft cover on 944 models, with notes on the 1985+ bearing cap seal and the two main seals that differ by 1 mm in outside diameter.

Covers correct installation of balance shaft sprockets using the woodruff key and 'O' stamping orientation, plus a visual alignment check procedure to confirm proper balance shaft timing at TDC.

Explains why the 944 uses balance shafts, how they work to cancel second-order harmonic vibrations, and the history of the system from Frederick Lanchester's invention through Mitsubishi's 'Silent Shaft' patent to Porsche's implementation.

Complete installation procedure for the camshaft timing belt and balance shaft belt on 944 and 968, including alignment marks, routing sequence, and crankshaft bolt torque.

Complete removal procedure for the camshaft timing belt and balance shaft belt on 944 and 968, covering all three tensioner types: eccentric roller (1983–86), spring tensioner (1987+), and hydraulic (968).

Procedure for setting, checking, and adjusting timing belt and balance shaft belt tension using Special Tool P9201, with specifications for new and used belts on all tensioner styles (eccentric roller, spring, hydraulic).

Maintenance intervals and complete parts list for camshaft and balance shaft belt service on 944 and 968 models, including part numbers for belts, tensioner rollers, and related hardware.

Spark plug replacement procedure with gap specification and torque, plus a diagnostic table for interpreting plug condition to identify engine problems.

Procedure for installing an all-metal or Teflon crank scraper on a 944 or 951 to reduce oil aeration and crankshaft windage drag at high RPM, including fitting, clearancing, and main bearing nut torque specifications.

Step-by-step procedure for installing the 944/951 engine from below, covering cross-member assembly, torque specs for all mounting hardware, and reconnection of all systems.

Oil and filter change procedure for the 944 and 944 Turbo, with part numbers for filter and drain plug seal ring, oil capacity, and torque spec for the drain plug.

Step-by-step procedure for removing the 944/951 engine from below the car, covering all disconnections, cross-member removal, and hoist techniques.

General troubleshooting guide for 944 starting and running problems, covering rough idle causes (temperature sensor, plug wires, O2 sensor, air flow box, idle stabilizer valve) and difficult starting causes (fuel pressure, DME relay, sensors, distributor).

Procedure for installing the flywheel lock tool (P9206) to hold the engine at TDC for torque-sensitive operations such as timing belt work.

Multiple methods for finding and setting TDC on cylinder #1, including the flywheel 'OT' mark in the clutch housing window, the camshaft sprocket alignment mark, and the wooden dowel method.

Symptoms and inspection criteria for worn 944 motor mounts, including the minimum height specification and a simple wire gauge check method.

Step-by-step motor mount replacement procedure for the 944, including jacking technique, bolt length selection for left vs right side, thread chasing tip, and all torque specifications.

Visual method for identifying whether a 951 is fitted with the early K26-6 or later K26-8 turbocharger using a distinctive flat spot on the turbine housing, inspectable without removing the turbo.

Complete removal and installation procedure for the 944 Turbo (951) K26 turbocharger, including parts list with O-ring and seal ring part numbers, and guidance for fitting an upgraded turbocharger such as the K27.