My YJ has the 19lb injectors, PDI ignition, 62mm TB. On 2/20/09 I got the thing smogged at the request of CARB/DMV
Here were the results:
CO2 O2 HC (PPM) CO % NO (PPM)
Test RPM MEAS MEAS MAX AVE MEAS MAX AVE MEAS MAX AVE MEAS
15mph 1790 14.6 0.0 93 19 91 .72 .06 .11 539 136 160 PASS
25mph 1789 14.7 0.0 58 12 58 .86 .05 .04 792 124 161 PASS
It passed. But like I said, it was close (So close, I am wondering if the SMOG test-only center I used was a "ringer" of some kind).
A few things might be contributing to the HC levels:
1) The cooling system mostly has water in it currently. I didn't have any coolant or mix on me the other day when I was low so I just used the water at an air/water station. I'm going to have to flush and refill the system.
2) I'd be surprised, but the intake/intake manifold wrap I use has might be keeping intake air pretty cool and causing a slightly rich condition.
3) 19lb Injectors flow a little better, so maybe some of the fuel isn't combusted as thoroughly as before. But I doubt we're talking much of a difference. My last HC test I believe showed lower levels at 15mph and 25mph but I don't think it was a heck of a lot lower.
4) Dirty air filter. Doubt it though -- I'm using one of these in-line cotton gauze setups which filters for sh!t anyway
Will get in there and check the plugs this weekend. Mine are some version of Champion copper core plugs gapped at .065