In Reply to: emission test posted by Mike Fuller on June 06, 2000 at 19:47:07:
: hydrocarbons are unburned fuel therefore high hydrocarbon reading indicate a missfire either electronically caused or mechanical.
electronics could be a bad sparkplug,plug wires,bad dist cap,bad rotor,coilwire or coil,bad oxygen sensor,bad injector or injector driver in ECM.
mechanical problems could be burned exhaust valve,low compression,excessive oil consumption,bad idle speed control motor(sticking open causing lean missfire),bad or leaking injector, vacuum leaks(intake gaskets?),to lean a mixture causing missfire,plugged air filter,bad airflow meter (air door flap not moving properly),etc.
what were the other readings,you have to look at the whole picture do they give you a CO,CO2 and O2 readings did it fail at idle of at road speed?
adjusting the idle wont have any affect unless your idle speed control motor is bad as it controls the idle speed via the computer
how does the car run does it seem to be missing?does the car have a catalytic converter US cars need a working cat to be clean enough to pass US emissions standards.