I’m having a issue with my ddec 4 I have repeated engine codes going on. Here’s what’s happening the truck idles rough up to about 1k rpm in park position runs fine going down the road. My mehanic at the terminal is saying it’s a optimized idle issue from the the ecm, but the kicker my truck doesn’t have that feature. So before I shell out for a new ecm, could this possible be a swapped ecm that’s causing this issue?
Thanks in advance for your help