Boost pressure regulator (VW Golf 3)

The selected turbocharging design has the advantage that already at a relatively low speed the boosted air enters the cylinders, which means that at high speeds there is too much air in the cylinders. The pressure in the boost system can rise so much that it is detrimental to the service life of the engine. The task of the boost pressure regulator (3) is to prevent this. It ensures by opening the valve that only part of the exhaust gases passes through the turbine wheel of the boost system. The boost power drops and the pressure cannot increase by more than 0.83 bar.

Note: What turbocharging does not like at all is engine stalling after a long period of driving at full throttle. This can lead to coking of the system when treated this way: the shaft bearing near the turbine wheel heats up so much due to the unexpected influx of heat that all the oil in the bearing burns and hardens. The more often this happens, the sooner the turbocharging will fail.

Therefore, after a long period of driving at full throttle, the engine should idle for some time. Before replacing a suspected turbocharger, it is necessary to check and be sure that the following systems are working properly: injection timing, fuel supply, full load limiter, compression, air filter and possible leaks in the intake and exhaust tract.