I have a 2003 DTS (obvious) changed the 2 crank sensors and the tps sensor. Still idles rough and shuts down. Took the car apart to double check the sensors black on bottom grey on top. still throws ses code "idle lower than expected. It's random some times runs fine sometimes horrible. check iac valve seems to be working fine. reset the valve runs great for about half an hour then back to the same thing. Any help would be appreciated!!!!!!

 

Check for carbon build up at throttle plate (butterfly), vacuum leak at bottom of the boot that connects intake to crossover, and EGR valve that is not closing.