Evap Canister And Leak Detection System Hose Routing; Leak Detection System - Audi Q7 2007 Repair Manual

4.3 EVAP Canister and Leak Detection Sys‐
tem Hose Routing
Note
The hose diagram shows the 4.2L FSI engine.
1 - EVAP Canister Purge Reg‐
ulator Valve 1 - N80-
❑ Installed location: on the
right side of the engine
compartment in the
rear.
2 - To Fuel Tank Filler Tube
3 - EVAP Canister
❑ Component location:
under the wheel hous‐
ing liner inside right rear
wheel housing.
4 - Air Filter
❑ For the Leak Detection
Pump - V144-
5 - Leak Detection Pump -
V144-
❑ Component location:
under the wheel hous‐
ing liner inside right rear
wheel housing.
❑ Checking in
Guided
-Vehicle Di‐
Functions
agnostic Tester- .
6 - Throttle Valve Control Mod‐
ule - J338-
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4.4

Leak Detection System

Function
The leak detection system recognizes leaks in the complete fuel
system, including the fuel tank, EVAP canister and EVAP Canis‐
ter Purge Regulator Valve 1 - N80- .
On the mechanical side, the leak detection system consists main‐
ly of a vacuum-driven diaphragm pump, that is equipped with a
reed contact on the actuation rod of the pump diaphragm. The
pump is supplied with vacuum via the engine intake stroke.
♦ When leak detection is activated, the diaphragm pump pumps
the fuel system up to 20 to 30 mbar. The pump diaphragm is
Audi Q7 2007 ➤
Fuel Supply System - Edition 10.2018
4. EVAP Canister and Leak Detection System
63