Fail Emissions...high HC

[PacoLoco]

I had to take my SHO for an emissions test and failed. The HCs was a 1.97. The standard is .9. Obviously, I'm not burning all of my gasoline. I'm going to check the ohms on my spark plug wires and make sure that there ok. I'm pretty sure that the wires can't be the only problem. I changed the spark plugs like a wefek ago, so they should be okay. What else can I do before I take it to a shop? The check engine light goes on every so often when i'm driving. The code is 556. Also, the SHO burns oil. From the looks of it, it's because of the valve seals. Can this cause my HCs to be high? Probably not. What tests can I perform on the SHO to figure out what's wrong and why the HCs are high? (I have a 93 SHO MTX, 110,000)

 

[TYSHO]

Disconnect the battery, ground, for at least 10 minutes. After that re-run the codes and see what you get. I had the same problem and it was just the O2 sensors, causing a rich condition. But this can be other problems just as well.

 

[Rob94]

Oil is a hydrocarbon. If you are burning oil, then yes, it COULD be causing higher readings.