3308484 - 1048B pressure air circuit

VIEW OF ASSEMBLY

- 1, Air/air heat exchanger (intercooler) 2, Supercharging air by-pass valve 3, Air flow meter ( See subassembly 1056 PETROL INJECTION SYSTEM ) 4, Air temperature sensor ( See subassembly 1056 PETROL INJECTION SYSTEM ) 5, Butterfly casing integrated with D.V.L. ( See subassembly 1056 PETROL INJECTION SYSTEM ) 6, Turbocharger ( See subassembly 1064 ENGINE TURBOCHARGING SYSTEM ) 7, Supercharging pressure control solenoid valve (overboost), ( See subassembly 1064 ENGINE TURBOCHARGING SYSTEM )

SUPERCHARGING AIR BY-PASS VALVE

This has the task of cancelling the "ram effect" which occurs each time the accelerator pedal is released sharply when the engine is supercharged.When the butterfly valve closes, a vacuum is created in the air chamber.This vacuum, detected by means of a special pipe, opens the by-pass valve.In this way the pressure upstream of the (closed) butterfly can be discharged via the by-pass, into the inlet manifold.