Getting better with age. Emissions.
I just had the 3rd emissions test done on our car.
When we bought it off the car lot it had some border line numbers but I wasn't too concerned. The second test I was worried about failing due to the just sqeaking by on the first one.
To my surprise it passed with better numbers.
About this time I switched to 5w30 Mobil 1.
I've also since dropped in Bosch Platinum +4's and replaced the EGR valve. May have or may have not been a factor but I thought I'd mention it.
Limits for HC is 72, CO is 0.40, NO is 531.
1st test in 1999, HC = 72, CO = 0.11, NO = 329 @ 60,000km's
2nd test in 2001 HC = 38, CO = 0.11, NO = 129 @ 85,000km's
3rd test in 2003 HC = 21, CO = 0.04, NO = 90 @ 128,000km's