If memory serves me right they said it was the hydro carbons and that it barely failed. They told me to add a fuel additive and bring it back but it didn't pass again but it was closer. The car had been sitting in a garage and almost never used for the past few years. The shop said I should get the spark plugs changed and that would possibly allow it to pass. Does this sound right? Anything else I should try? I could add diagnostic stuff later I just don't have it right now.
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If the car was sitting for a while yes I would agree do a minor tune up at least also try higher octane gas at least while you have it tested. Good news is you only have two more years and you won't have to do emissions inspections anymore.
When Hydrocarbon (HC) emissions are high, that is a result of an engine misfire, excess fuel entering the cylinders, or a catalytic convertor not working as well as it should. Replacing the plugs is a good place to start, perhaps the 02 sensor as well if it is not to expensive and relatively easy to replace. Make sure you make a good freeway run before getting the vehicle tested, you want to be sure the catalytic convertor is fully warmed up and functioning at its best. If you still don't pass you can plug the results of the test into a Lamda calculator - http://www.smogsite.com/calculators.html#lambda. This calculation will help determine if the problem is to much fuel or something else (misfire or tired cat).
Great advice guys thanks for the info. I liked at my report and everything passed except the HC ppm. The limit is 172 and my reading was 188. Sound like plugs and wires and a new cap might do the trick?
Great advice guys thanks for the info. I liked at my report and everything passed except the HC ppm. The limit is 172 and my reading was 188. Sound like plugs and wires and a new cap might do the trick?