My friend has a '93 honda civic 4 cyl. Totally stock. He failed his HC ppm and CO % but barely passed the NOx ppm. I helped him change the cat. It now passed the HC ppm and the CO% but failed the NOx. The part store says this car doesn't have a EGR Valve so I'm at a loss as what to do to get the NOx down.
Can some one help?
have the same problem?
Friday, May 7th, 2010 AT 11:23 PM