Toyota Land Cruiser 1988 Repair Manual page 39

EM-8
Check Connector
ENGINE MECHANICAL- Engine Tune-up
INSPECTION AND ADJUSTMENT OF
IGNITION TIMING
{See steps 10 to 14 on page IG-11)
Ignition timing:
7o BTOC
@
idle
(w/ Terminals TE1 and E1 short-circuited)
IDLE HC/CO CONCENTRATION CHECK
METHOD
NOTE: This check is used only to determine whether or
not the idle HC/CO complies with regulations.
1. INITIAL CONDITIONS
(a) Engine at normal operating temperature
(b) Air cleaner installed
(c) All pipes and hoses of air induction system con-
nected
(d) All accessories switched OFF
(e) All vacuum lines properly connected
NOTE: All vacuum hoses for EG R systems, etc. should
be properly connected.
(f) EFI system wiring connectors fully plugged
(g) Ignition timing set correctly
(h) Transmission in "N" range
(i) Tachometer and HC I CO meter at hand and cali-
brated
2. START ENGINE
3. CHECK OXYGEN SENSORS OPERATION
(a) Using a service wire, short terminals TE1 and E1 of
the check connector.
(b) Connect the positive ( +) probe of a voltmeter to
terminal VF1 (VF2) of the check connector, and
negative (-) probe to terminal E1.
(c) Hold the engine speed at 2,500 rpm for approx. 2
minutes.
(d) Then, maintaining engine at 2,500 rpm, count how
many times needle of voltmeter fluctuates between
0 and 5 V.
Minimum needle fluctuation:
8 times for every 10 seconds
If the fluctuation is less than minimum, check the air
induction system for leakage. If necessary, see EFI SYS-
TEM.