Boost Pressure Control System Check - Mitsubishi Lancer Evolution-IV Workshop Manual

INTAKE AND EXHAUST –
(3) If the boost pressure is lower than the standard value,
(4) If the boost pressure is higher than the standard value,
2. BOOST PRESSURE CONTROL SYSTEM
Wastegate
solenoid valve
(1) Disconnect the hose (black) from the wastegate solenoid
(2) Connect a hand vacuum pump to the three-way joint.
(3) Disconnect the hose (black) from the intake pipe nipple
(4) Disconnect the negative cable from the battery, keep it
(5) Block and unblock the end of the vacuum hose (black)
On-vehicle Service
check for following which are probably the cause:
D
Wastegate actuator inoperative
D
Boost pressure leak
D
Turbocharger defective
boost pressure control is probably faulty. Make the
following checks:
D
Wastegate actuator inoperative
D
Wastegate valve inoperative
D
Wastegate actuator rubber hose disconnected or
cracked
CHECK
valve and connect a three-way joint between the hose
and solenoid valve.
connected to the turbocharger compressor housing and
fit a blank plug to this nipple.
disconnected for 10 sec. or more, and then reconnect
it back again.
with a finger to apply vacuum and check for the vacuum
condition.
Engine condition Hose (black) end
Stationary Unblocked
(ignition switch: ON) (ignition switch: ON)
Blocked
Idling after warmup
NOTE
If the vacuum condition is faulty, the wastegate actuator,
wastegate solenoid valve, or hose is probably defective.
15-3
Normally
Vacuum leaks.
Vacuum retained.
Vacuum leaks.