CA Smog Nightmare: Please Help!
I've been lurking on the forum now for about 6 months as I restore my '95 SS. The information here has been completely spot on and amazing in helping me get this beast back on the road. Try as I might searching myself, I can't really figure out how to attack the following problem:
My car passed the emissions portion of the smog test with CARB-illegal long tube headers. Due to the fact that these headers had no provision for the AIR pump (not deleted, but just venting to atmosphere) it failed the visual inspection.
I went and searched out the CARB-legal headers, and after much wresting (and a ton of money) they have been installed. I also completely replaced the EVAP canister, purge valve, and all of the accompanying hoses. Fully re-welded the exhaust including brand spanking new cats (now with ~100 miles on them). Now the car won't pass emissions due to NOx. All of the other emissions readings for CO2, 02, HC, and C0 pass with flying colors. The only bad one is NOx. And I'm talking a ton of NOx.
With the "illegal" setup, we were looking at:
MAX: AVE: MEAS:
15mph: 677 267 0
25mph: 680 248 15
With the "legal" setup, we are looking at:
MAX: AVE: MEAS:
15mph: 677 267 635
25mph: 680 248 1114
It's almost as if the EGR is not working whatsoever. But I can almost stall the car by manipulating it by hand, making me think it's operational. I have no CEL.
I did hook the car up to Freescan to see I there were any DTCs, and the only one I got was a CODE 18 (relating to the injector circuit). Coolant temperature looks great according to Freescan as well.
I'm not an expert at what the 02 sensor data should be say, but I know it's supposed to bounce around, which it is doing. It's not flattening out under load or anything like that.
I just blasted a can of Seafoam through the brake booster hose out of desperation today, but other than that I'm stumped. Any ideas out there?
- A guy who just wants to drive his damn car!
1995 SS: F-Body bucket seats, 9C1 rubber floor, black billet grille, smoke headlights with HID conversion kit, 13" grant steering wheel, cold air intake, 50-state hooker headers, probably some other stuff done to it that I don't even know about...