My 2012 Kia Soul+ (53,700 miles) failed the emissions test for high HC and high CO at high RPMs (2500). After a new air filter, spark plugs, a professional injector and throttle body cleaning, the motor runs like a champ. Nonetheless, it failed emissions again, this time just for CO, but it was high both at idle and 2500 RPMs (not just high RPMs, like the first time. The stats are below. Oddly enough, the CO emissions went even higher after the new plugs and cleaning!

Oh, and no codes are coming up.

So, any idea what's going on? My first thought was to replace the oxygen sensors, which I can get easily. Besides that, I can only think of the catalytic converter, but the local Kia dealership says that will take about 60 days to order a replacement where I live (Ecuador, South America). I only get one more try before my car is considered "decomissioned" and will need to pay a big fine. I also don't want to wait 2 months for a cat replacement, if possible. Any other ideas before I go down that road would be greatly appreciated. Thanks! Emissions 2015-2018

  • Possible duplicate of Emissions - High CO reading only – GdD Oct 11 at 8:17
  • Welcome to the site @ScottGibson. High CO has already been asked, so this is a duplicate. Have a look at the answers on this: mechanics.stackexchange.com/questions/42985/… – GdD Oct 11 at 9:00
  • Welcome to the site. Do you know if your EGR (exhaust gas recirculation) system is healthy? Have you noticed any degradation in fuel economy compared to 2015? – Zaid Oct 11 at 13:41
  • Looks like you have a damaged catalyst. can you get hold of a second hand one off a breaker yard? – mx5_craig Oct 11 at 20:19

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