Toyota 4-Runner 1985 Repair Manual page 134

EC-34
EMISSION CONTROL SYSTEMS (CARB.) -
Exhaust Gas Recirculation (EGR) System
COLD
3,000 rpm
Tachometer
HOT
3,000
rpm
Tachometer
ECl192
EC1052
Vacuum Gauge
EC0137 EC0128
High Vacuum
Vacuum Gauge
EC0137 EC0130
EC10S3
INSPECTION OF EGR SYSTEM
1.
PREPARATION
(a) Disconnect the hose from the distributor malt ,-
diaphragm, and plug the hose end.
A03052
(b) Using a 3-way connector, connect a vacuum gauge
to the hose between the EGR valve and EGR vacuum
pipe.
2.
CHECK SEATING OF EGR VALVE
Start the engine and check that the engine starts and runs
at idle.
3. CHECK BVSV WITH COLD ENGINE
(a) The coolant temperature should be below 30°C
(86°F).
(b) Check that the vacuum gauge indicates zero at
3,or
rpm.
4. CHECK BVSV AND EGR VACUUM MODULATOR WITH
HOT ENGINE
(a) Warm up the engine.
(b) Check that the vacuum gauge indicates high vacuum
at 3,000 rpm.
(c) Disconnect the vacuum gauge and reconnect the
vacuum hose to the proper location.
5. CHECK EGR VALVE
(a) Apply vacuum directly to the EGR valve with the en-
gine idling~
(b) Check that the engine runs rough or dies.
(c) Reconnect the vacuum hoses to the proper locations.
IF NO PROBLEM IS FOUND WITH THIS INSPECTION, THE SY ...
TEM IS OKAY; OTHERWISE INSPECT EACH PART