5000S Sedan L5-2226cc 2.22L SOHC (KZ) (1985)
Idle Speed: Testing and Inspection
TEST CONDITIONS
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engine oil temperature minimum 80°C (176°F)
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ignition timing OK
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A/C switched OFF
WORK SEQUENCE
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connect tester VW 1367 using cable adapter US 1112
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push % button on VW 1367
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check duty cycle
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specification: 28 ± 12% (with oxygen sensor connected)
If NO
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adjust duty cycle If still NOT OK, and duty cycle reading is 33% or 40%
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check that A/C is switched OFF
If A/C OFF
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check idle switch for function or for open circuit between idle switch and control unit connector
If cycle reading fluctuates irregularly between 25% and 20%
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check for open rpm signal circuit from electronic ignition control unit
If duty cycle reading is 25%
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idle speed incorrect
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check for leaks at throttle body gaskets and seals
If NO leaks present
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check for open circuit between idle stabilizer and control valve.
If circuit OK
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replace control valve
A/C SWITCH SIGNAL, CHECKING
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switch A/C ON
^
rpm boost approximately 100 rpm
If NO
^
check for open circuit between dash switch and control unit connector terminals 6 and 16
A/C COMPRESSOR SIGNAL, CHECKING
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switch A/C ON
-
A/C compressor has switched OFF
^
rpm boost approximately 100 rpm
If idle increases over 1,000 rpm with A/C compressor OFF