Assuming this is a 2.3. The timming I think can be set by turning the distributor. The fuel mixture can be changed by turning the 3mm allen bolt in the lambda tower under the air cleaner housing. You will need a lambda meter to do this. The Normal operating range for this assuming it is a 2.3 will flucuate because it has an electromagnetic clutch on the engine coolant fan that engages at about 100c-105c and turns off at about 80c.
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