Diagnostic Procedure 19 — Surge
EF & EC-461flowchartCHECK EXHAUST GAS SENSOR step applies to models with catalyzer only. Two alternative methods given: with CONSULT diagnostic tool, or without CONSULT (using self-diagnostic Mode II).
Diagnostic Procedure 19 — Surge
1
CHECK EXHAUST GAS SENSOR. (MODELS WITH CATALYZER ONLY) [With CONSULT] 1. See "M/R F/C MNT" in "DATA MONITOR" mode. 2. Maintaining engine at 2,000 rpm under no-load (with engine warmed up sufficiently.), check to make sure that the monitor fluctuates between "LEAN" and "RICH" more than 5 times during 10 seconds. RICH->LEAN->RICH-> (1 time, 2 times) LEAN->RICH....... OR [Without CONSULT] 1. Set "Exhaust gas sensor monitor" in the self-diagnostic Mode II. (See page EF & EC-412.) 2. Maintaining engine at 2,000 rpm under no load, check that the RED L.E.D. on the E.C.U. or the check engine light on the instrument panel goes ON and OFF more than 5 times during 10 seconds.
N.G.
Replace exhaust gas sensor.
O.K.
2
TRY A KNOWN GOOD E.C.U.*
Trouble is not fixed.
INSPECTION END
Trouble is fixed.
3
Replace E.C.U.
NOTE
*: E.C.U. may be the cause of a problem, but this is rarely the case.