I have LT ypipe and O2 sims on a 96 and have passed emissions for two years. I went last week and it shows EGR, o2 heat and cat as incomplete. I do believe that when it was in the shop the week before that the batt was disconnected, but am not sure. If you have LT1 edit deleting the EGR and AIR, how does the drive cycle complete? It must have somehow in the past, but I have driven over 100 miles (traffic though) and it is still not ready. The mechanics (dealer, but very good and only guys that touch it in the shop) were not sure how it would possibly finish since the o2 heat was dependent on EGR and then cat was dependent on o2. I am runnning out of time to renew and Ion sent me a tune with the EGR and AIR back on, but will it work?

thanks guys

 

I had the same problem about three weeks ago when I went in for emissions and I got the same 3 Not Ready codes. I did however take the car in prior to installing a new PCM from Madz28 so the car didn't go through all of its cycles yet apparently. I drove the car for a solid week doing short and long trips and I passed with flying colors. If your battery was disconnected, it may have forced the PCM to have to do a "relearn" phase. Drive the car for a few more days and see what happens.

 

Have you already tried a couple GM drive cycles? www.obdii.com/drivecycle.html

 

I tried the hard cycles on Tues and it had not set yesterday. I had driven for a week and about 100 miles at that point. I guess a long highway drive is in order for me. But how does it learn if stuff is off?