Just got back from 1st smog check. My 77 280z failed. Here are the numbers:

MPH / HC-max-meas / CO-max-meas / NO-max-meas

15 / 214 - 269 / 1.36 - 6.39 / 1364 - 209

25 / 181 - 256 / 1.16 - 6.39 / 1224 - 197

More data input about the car:

• New afm

• New fuel injectors

• New water temp sensor

• New thermostat

• 75000 mileage

• Has cold air intake

• Timing is set at ZERO (which needs to be fixed)

The guy at the shop basically said that i'm running too rich. Are there any suggestions on where i can start problem solving. Any help is much appreciated.

Thanks

Oh, one more bit of data. I currently get 20mpg. I thought this was pretty good relative to what others on the forum are getting, but apparently its still running rich.

Thanks once again.

I am not very well versed on this but know some basics,

Sblake01 can chime in on this when he sees it. I beleive the problem lies in the air regulator adjustment screw inside the A.F.M. If you are on the drivers side looking at the afm, there should be a little rubber plug covering the screw, towards the bottom rear of the unit.

You really need do measure the CO reading with an instrument. There is no "proper setting" for the screw from what I've been told, and playing with it without the proper equipment might do more harm than good.

What Mark says about the AFM is true. I wouldn't adjust it without a CO tester. And, even so, the fact that your HC and CO are up and your NOX is way down makes me wonder about the condition of you catalytic converter rather than the AFM adjustment. The timing being at 0 doesn't help either.