100CS Quattro Wagon V6-2.8L (AAH) (1992)
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Find and eliminate open or short circuit in wiring between MAF sensor connector and ECM connector A.
MAF sensor
ECM connector A
connector
1
2
2
5
4
1
Note:
Use only gold-plated terminals when replacing mass air flow sensor connector terminals.
Checking function of MAF sensor
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Push back protective boot on MAF sensor connector (leaving sensor connected).
Note:
The connector terminals are appropriately identified on the back of the connector:
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Connect multimeter (Fluke 83 or equivalent) between connector terminals 2 and 4, using adapter cables from VW 1594 connector test kit.
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Switch ignition on.
Specified value: 1.0-7.5 volts
If specified values are not obtained:
The CO% potetiometer is faulty. Replace mass air flow sensor.
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Connect multimeter (Fluke 83 or equivalent) between connector terminals 2 and 1, using adapter cables from VW 1594 connector test kit.
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Switch ignition on.
Specified value: 0.3-1.1 volts
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Let engine run, switch all electrical consumers off (radiator cooling fan must not run) and vary engine speed continuously between idle and
4000 RPM.
Specified value: voltage must vary between 1.5 to maximum 3.4 volts, corresponding to engine speed.
If specified values are not obtained:
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Replace mass air flow sensor.