Volkswagen 1.4-ltr. 16V 55kW Engine Technical Guide

Important Information

This document is a Self-Study Programme designed for technical training and service reference. It is not a workshop manual. It covers the design and function of the 1.4-ltr. 16V 55kW engine, which features significant design changes compared to previous generations, such as roller-type cam followers and a plastic intake manifold.

Engine Mechanics

The engine features a die-cast aluminium crankcase and a plastic intake manifold, which reduces weight by approximately 36% compared to aluminium versions. The valve gear utilizes roller-type cam followers with hydraulic support elements to reduce friction and moving masses.

Crankshaft and Sealing

Warning: The crankshaft in the 1.4-ltr. engine must not be removed or loosened. Loosening the bearing cover screws causes the aluminium bearing seat structure to relax, resulting in permanent deformation of the crankshaft. If the bearing cover screws are undone, the crankcase must be replaced complete with the crankshaft.

Toothed Belt Drive

The drive system is divided into a main drive and a connecting drive. The main drive connects the crankshaft to the coolant pump and intake camshaft. The connecting drive connects the intake camshaft to the exhaust camshaft.

Engine Management

The engine uses the Magneti Marelli 4AV management system. Key components include:

• Engine speed sender G28: Scans a 60-2 sender wheel on the crankshaft.
• Hall sender G40: Located on the intake camshaft to determine cylinder-selective knock control and sequential injection.
• Static high-voltage distribution: Uses an ignition transformer located at the end of the camshaft housing, eliminating the need for a distributor.

Service and Maintenance

For repair work, specific special-purpose tools are required, including the T10016 camshaft locking tool, T10017 assembly device for the sealing flange, and T10022 sleeve/thrust piece for the crankshaft sealing ring. Only G12 coolant additive is approved for use to prevent corrosion.

Self-Diagnosis

The engine management system supports self-diagnosis via V.A.G. 1551, 1552, or VAS 5051. Functions include interrogating fault memory, actuator diagnosis, basic adjustment, and reading measured value blocks.