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Old 09-25-2002, 08:03 AM
mbdoc mbdoc is offline
Join Date: Mar 1999
Location: Tucker, Ga USA
Posts: 12,153
Have had that problem on several 1990 & 91 cars. The O2 heater must work so that the O2 sensor gets hot enough to go into "closed loop". The heater must receive battery voltage from the MAS relay. Many times the O2 sensor heater only gets 6-7 volts & LAMDA never works properly.
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