My Bravada failed only hydrocarbon. MAX Allowed was 100... my results showed 151 ppm. The oil was changed 1000 miles ago. I put new plugs, wires, rotor, distributor and cap. New air cleaner and gas cap and new 02 sensor (Bosch). Hydrocarbon is carbon plus hydrogen (that's easy). How do I lower the hydrocarbons to pass smog test? (that' hard)! Answer:
We need to find out if your Oldsmobile is in proper fuel control as part of
the high HC diagnosis. This includes ensuring the oxygen sensor is working
properly, your vehicle's emissions computer is receiving the signals from
the oxygen sensor, the computer is computing the data properly and sending
the correct signals to the fuel injectors to either increase or decrease
fuel delivery to the combustion chambers. The problem may be more
complicated then simply changing emissions components.
posted by SmogTips Support
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