Q: I have a 1.6fe Toyota Conquest which is consuming too much fuel and engen vibrates and black smoke high idle 1995 Toyota Conquest

Hi there - first task is to get any problem code information available, whether the Check Engine light is illuminated or not. 1995 was an On-Board Diagnostics (OBD) year for many manufacturers, and your Conquest could have either OBD I or OBD II. If there is no OBD port under the dash, there should be a plastic box with "Diagnosis" stenciled on it under the hood on the left front wheel arch. Your rich mixture and rough running are possibly the result of a bad coolant temperature sensor (or wiring) reporting "cold" to the engine when, in fact, it isn’t. A bad oxygen sensor (pre-catalytic converter) or mass air flow sensor could also cause this problem. I recommend a high fuel consumption inspection performed by a mobile, professional mechanic, such as one from YourMechanic, who will come to your location, diagnose this problem, and give you an accurate assessment of damage and cost estimate for repairs.