Thank you for your answer. The engine is carburated, recently it's been tuned up, cleaning carburator and replacing sparks. It has 320.000 Km on it (about 200.000 milles). The last owner told me the engine was rebuilt on 2002 because the oil level was going down between oil changes. The car makes 30 Km with each gallon average (30 km = 18 Mi (1.6Km/Mi)). I think we're not talking about US gallons, just gallons (4 liters).
Regards,
David.
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