I just installed a new 408, a new tranny, new DTE Rear-End, new stall, new suspension and a new fuel system. Car ran great for about 5 miles, now it stalls. I'm running open headers, the rear O2's are turned off. Could me being opened headers be the reason my car stalls after about 20 sec. of idleing, or as soon as you go to put it into gear..?

 

ttttt

 

Are your front O2s still operational?
Open headers will fry those quickly, check for any codes related to O2s

 

No codes, but I can get new ones though. How can I know if these are good or bad???