I have an 81 242 manual shift that just failed VA emissions with the followinge levels:

15mph
HC ppm - 49 (125 limit)
CO% - .07 (1.26 limit)
**NO ppm - 1012 (972 limit)**

25mph:
HC ppm - 46 (121 limit)
CO% - .07 (1.54 limit)
**NO ppm - 1053 (885 limit)**


Being so comfortably under the limit on HC & CO readings is somewhat reassuring, but obviously I need to deal with the NOx. I've read through the archivs and found some helpful information (esp. thread http://www.brickboard.com/RWD/index.htm?id=683776)

My questions are:

1)- In what may have been a foolish move, I added "The Outlaw" octane boost a few days ago. The car hasn't been getting driven much lately, and I figured it would help clear things out. Could this alone be the problem?

2)- I drove the car for about 20 minutes before going in for the test, and left it at idle for almost 45 mins while I waited in line. Is it likely that a longer drive will help?

3)- my other numbers are pretty good, so I'm hoping that indicates something smaller than the cat.

4)- The limit for NOx gets lower as speed increases, but my emissions go up. Is that an indication that this probably IS the cat, and not something smaller?

5)- if it is the cat, I read in the archives that someone just banged on theirs to loosen things up, and they passed. Am I close enough to the limit to where this could work?

thanks for your help.

-Alex