Hello all, in a couple of days I will be going in for my third ref appointment. I have an OBD1 JDM (P72) B18c in a 93 integra and, as the title says, it wont pass the sniffer test. A quick rundown on my setup: I have the CARB legal Skunk2 IM, stock exhaust (including the manifold), stock intake plumbing with a K&N drop in, USDM GSR ECU, and all of the correct wiring and vacuum lines hooked up, always use 91. Here's the numbers from the first test

15 mph
CO2=14.2; O2=0.6; HC Max=89, Meas=151; CO Max=0.53, Meas=0.64; NO Max=708, Meas=2627 GROSS POLLUTER
25 mph
CO2=15.0; O2=0.1; HC Max=54, Meas=69; CO Max=0.51, Meas=0.16; NO Max=746, Meas=716 Fail

OK so the first test the 15 mph failed miserably. The NOx made me a gross polluter! So after this I did a major tune up. I changed the plugs, oil, checked (and cleaned)the wires/cap/rotor (all recently changed), new cat, new NTK O2 sensor, new pcv valve/hoses and block breather, new fuel filter, ran seafoam on one tank and Lucas fuel system cleaner on another, cleaned the TB and IACV, new thermostat, and used a bottle of HEET in the fuel I used on the second test, and here are the results from all this work:

15mph
CO2=14.8; O2=0.3; HC Max=89, Meas=128; CO Max 0.53, Meas=0.34; NO Max=708, Meas=2731! GROSS POLLUTER
25 mph
CO2=15.2; O2=0.0; HC Max=54, Meas=45; CO Max=0.51, Meas=0.11; NO Max=746, Meas=737 Pass

So I'm getting a little closer, I actually passed the 25 mph test! But now what!? I Know that high combustion temps/ compression yield higher NOx numbers but timing is right at 16 degrees and with all of this new crap I figure it should pass! I have a couple theories as to what the problem is.
1. I didn't wire something correctly that wouldn't throw a code if it were bad (i.e. purge control solenoid)
2. Bad coolant temp sensor? My fan never kicks on and my system has to relieve pressure often (but never overheats/goes passed half way mark on gauge)
3. Vacuum leak somewhere? I sprayed carb cleaner anywhere and everywhere there could be a vacuum leak and there was no change in idle speed. There is however a slight surge when I hold the throttle at any rpm. My buddy brought home a smoker from his shop and we didn't see anything (car was still hot though which sometimes makes it hard to see the smoke)
4. Bad or going bad sensor? Maybe a bad MAP sensor or TPS, IAT, etc?

Sorry this is so lengthy, if you made it this far I appreciate your time. I'm just really in a bind. The DMV said they wont give me anymore extensions and I have a month left. Not to mention I'm kinda broke, so I can't afford to blindly throw money at new sensors and crap that don't need to be changed. If you have any input it would be greatly appreciated.
Thanks,
Eric