*If charge air pressure is too high, fuel supply will be interrupted in order to protect engine. This results in
Charge air pressure below specification
Wastegate bypass regulator valve N75 faulty -
->
Wastegate bypass regulator valve N75 ,
checking
, checking
Hoses to Wastegate bypass regulator valve
N75 faulty, -->
Boost pressure regulation
and vacuum control system, connection
diagram for vehicles up to 06.03
,
connection diagram or -->
Boost pressure
regulation and vacuum control system,
connection diagram for vehicles as of
07.03
, connection diagram
Charge pressure control valve in turbocharger
sticking in open position
Leak between turbocharger and intake
manifold -->
Effects of leakage at intake
and exhaust end
, effects
Mechanical air recirculation valve faulty -->
Mechanical air recirculation valve,
checking
, checking
Recirculating valve for turbocharger N249
faulty -->
Recirculating valve for
turbocharger N249 , checking
, checking
Turbocharger faulty -->
Turbocharger,
removing and installing
, replacing
Charge air pressure above specification * See note
Vacuum unit for charge air pressure control
valve faulty -->
Turbocharger, removing
and installing
, replacing
Hoses to vacuum unit for charge air pressure
control (via N75 leaking -->
Boost pressure
regulation and vacuum control system,
connection diagram for vehicles up to
06.03
, connection diagram or -->
Boost
pressure regulation and vacuum control
system, connection diagram for vehicles as
of 07.03
, connection diagram
Charge air pressure control valve in
turbocharger sticking in closed position -->
Turbocharger, removing and installing
,
replacing
2005 Audi A4 Quattro
ENGINE 1.8 Liter 4-Cyl. 5V Turbo Engine Mechanical, Engine Code(s): AMB
1:01:17 AM
Page 212
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