Usually high HC is caused by a defective engine ignition system. Out of the
three systems your Ford's engine relies on to produce combustion (air
intake, fuel delivery, and spark control), the spark system has the
components which require replacement most often. Sparkplugs and spark wires
are constantly exposed to high temperatures and high voltages. You must
ensure your engine's ignition system is functioning properly, by inspecting
all the sparkplugs and their wires. If any of the plugs look worn out or
have excessive carbon build-up replace them immediately. You may use any
brand of product designed to work in your vehicle. The distributor cap
should also be inspected for cracks or excessive carbon deposits. If it
appears that the cap may be faulty, you will need to replace it. More then
likely you will see an instant performance increase once these corrections
are made.
There might also be a possibility that your Ford pickup's high HC problem is
CO related. There is a condition called the "Rich Misfire" your Ford might
be suffering from. This condition is created, when for any reason, the
combustion chambers receive too much fuel, causing the fuel that is
delivered to burn improperly and leave behind high levels of raw fuel(HC)
and partially burned fuel(CO). Vehicles producing high HC for fuel
management reasons usually begin producing normal HC levels once the fuel
problems are corrected. However in this case if the smog test results showed
normal CO emissions, then look closer at the engine ignition system.
