Robert,I use a dremel tool to burnish the contacts and then I spray Caig DeOx , a product used in electronics to treat the terminals.This is safe for all electrical and electronic use.
To Benzmac, the O2 sensor is new and is good. We checked the relays by substituting good ones from another car. Im afraid we will have to go to the dealer to check the computer. We will keep you updated


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jdk