Hey Everyone, I just got back from doing the emission test on my '94 Wrangler YJ, 2.5L, Auto. What follows are the results:

25/25 test 50/15 test

HC ppm reading 35, allowed 180 - passed, HC Read 31 allowed 185 passed

CO% reading 0.05, allowed 2.03 - passed, CO " 0.15 " 1.57 passed

NOX ppm reading 1387, allowed 1163 - FAIL, NOX " 630 " 1273 passed

rpm reading 2003, allowed 3000 - passed, rpm " 1605 " 3000 MAX
.
CO+CO2% reading 14.55 allowed 6.00-MINIMUM CO+cO2 14.59 6.00 MIN.

The main problem is the NOX, it failed.

Anyone have any ideas? I just put that CAT on 3 years ago +/- couple mos. The only modification on the Jeep is headers and it passed last year with them on.

Did you get the exhaust good and hot before inspection? I had the same problem with the nox reading a couple of years ago, failed miserably, I filled it up with Amoco Prem (now BP) & took it out on 85 and ran about 40 miles round trip right back to the inspection station. She passed with flying colors. Amazed the tech when I told him I had done nothing to correct the problem.