cat is brand new almost...i bought another anyways just incase and thats gona go on tomorrow...still its throwing the codes for the o2 sensors (13 and 63) which leads me to believe its the o2's

 

I would either replace the 02 sensors or just bring it to a gm dealer. They will probably still work on it with headers. They should be able to find a problem, your HC/CO readings at 25 mph are sky high. Don't get discouraged, the problem will surface sooner or later.

 

well i tried going to the gm dealership and they refused to touch it ( i tried two different ones ).....anyways ive been trying to fix this problem for awhile and im current a full time student so my dads been helpin me out with funds and hes sick of it....sooo it looks like im gonna have to end up selling it....we just put 2 new heated o2 sensors in it but to no avail.

 

I just skimmed over the entire post AGAIN and I didnt see where you got the car hot (to 210*) as suggested. So did you?

 

i put the stock t-stat in but the fans still come on early so it gets almost to 210 but certainly hot enough for the o2s to be working.

 

Since you are OBD1 maybe you could find someone to help you with a program thats should pass emissions and save you Ed Wright program for later.

 

its not obd1 its speed density...prom...i think the problem is the plugs that go in the back of the computer are worn and not making a good connection anymore....whenever u push on them while the car is running it makes it act up...

 

Acts up? Thats a problem. Install a manual fan switch to bring the temp up. And run Chevron supreme, it will also make a difference. Good luck.