External Links to a series of informative technical videos

Exhaust Gas Recirculation (EGR)
Function of EGR Cooler
Cleaning of Air Filters
Electric fuel pumps – blocked prefilter
Water pumps/ coolant pumps
Vacuum pumps
How does a vacuum pump work?
Vacuum pumps: Damage from lack of lubricating oil
OBD – On-Board Diagnostics Part 1: Introduction