Toyota 4-Runner 1985 Repair Manual page 139

EMISSION CONTROL SYSTEMS (CARB.)
Air Suction and Fuel System
Feedback Control System EC-39
2,000 rpm
Tachometer
EBCV
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EC1165
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EC0138 EC1166
About
300 rpm
Tachometer
EC1167 EC0141
Tachometer
EC1164 EC0140
Thermo
Switch (2)
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EC1168 EC11 00
Thermo Switch (1) '.'
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Bubbling Noise
Ground
EC1169 EC1161
INSPECTION OF FUEL FEEDBACK CONTROL
SYSTEM
CHECK FEEDBACK CONDITION
(a) Maintain engine speed at 2,000 rpm.
(b) Disconnect the connectors of EACV and EBCV.
A03057
(c) Wait a few seconds.
(d) Reconnect the EBCV connector and check that the
engine drops about 300 rpm immediately.
(e) Disconnect the vacuum hose from vacuum switch and
plug the hose end.
(f) Check that the engine speed return to 2,000 rpm, af-
ter few seconds.
(g) Reconnect the vacuum hose and connector to the
proper locations.
IF NO PROBLEM IS FOUND WITH THIS INSPECTION,
THE SYSTEM IS OKAY; OTHERWISE INSPECT EACH PART
INSPECTION OF EACV
CHECK EACV
(a) Disconnect the AS hose from the EACV.
(b) Disconnect the connector from the thermo switch (2),
and ground it.
(c) Check that a bubbling noise is not heard from the
EACV.
(d) Reconnect the connector to thermo switch (2).
(e) Disconnect the connector from the thermo switch (1 ),
and ground it.
(f) Maintain engine speed at above 1,390 rpm.
(g) Check that a bubbling noise is heard from the EACV.
(h) Reconnect the connector to thermo switch (1).
If a problem is found, replace the EACV.