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Home >> Mercedes Benz >> 1987 >> 420SEL (126.035) V8-4.2L (116.965) >> Repair and Diagnosis >> Powertrain Management >> Computers and Control Systems >> Testing and Inspection >> Component Tests and General Diagnostics >> Component Tests >> Air Injection System Test
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Air Injection System Test


Special Tools:





Equipment
- Multimeter -- e.g. SUN DMM-5

Y-distributor - 117 078 01 45:





Function Diagram, Air Injection, EGR And Fuel Evaporation Control System:





1 Fuel distributor
40 Diaphragm pressure regulator
77 Charcoal canister
78 Purge valve
79 Thermovalve 50°C
89 EGR valve
90 Vacuum amplifier
123 Throttle valve housing
125 Air pump
126 Air injection shutoff valve
127 Check valve (air injection)
128 Check valve (vacuum)
129 Timing chain housing cover
N1/2 Ignition control module
Y32 Air injection switchover valve
a from sir filter
b to fuel tank
c Vent line

Test Page 1:





Fig. 1:





Fig. 2:





Test Page 3: