My 1980 Chrysler LeBaron (V8 318ci) just failed an emissions test. I'm coming from a state without emissions testing to a state that requires it.
Specifically, the only part that failed was the hydrocarbon count. The legal limit was 300 PPM and the reading was 454 PPM. I passed the carbon monoxide test with a reading of 2.47% and a limit of 3%. Carbon dioxide was at 11.14%.
Some cursory reading seems to indicate that hydrocarbons are basically unburned fuel. So if there is too much of it coming through the tailpipe (where they measured), could something be wrong with the return line? Other reading suggested the catalytic converter might be at fault. When we replaced the exhaust pipe ourselves a year back, a visual inspection seemed to indicate that the grate in the catalytic converter was intact, not broken or rattling.
Given that I exceeded the hydrocarbon limit by 150%, it seems the fixes needed would be substantial. What could be causing such a high PPM of hydrocarbons given the information above, and what sorts of fixes would correspondingly be needed? Thanks in advance.