Ok so here’s what’s going on. All this idle issue started when I did the injectors. So what me and the mechanic are thinking was one of the owners before me had a tune in the truck because the old ecm was completely locked out. EFILive or someone key locked it at some point. I’m not sure I’m the 3rd owner. Bought it almost 5 years ago with 91k miles. Now has 171k.
So I did the injectors and idle issue started to happened. Changed everything listed in previous posts and nothing happened. I changed the ficm and brand new ecm stock tune. Now the truck runs great no issues so far drove 50ish miles. We know there was a tune in the truck before and now that it’s all back to stock I’m not sure if it was the ficm or ecm. So if your having the same issues as me i would definitely recommend doing a stock reflash/update. $200 at dealer. Clear your ecm that way you know your truck is stock tune and no tune stacking if you decide to tune your truck because like me if previous owners tuned it and didn’t tell you or don’t know or hide it or whatever just do the reflash and start at scratch. If that doesn’t work ficm on Lincoln diesel is $1200ish. Then get a new one if the reflash don’t work. It’s one or the other or both I’m not sure in my case because I did both at the same time.
The reason I’m posting all this information is because I don’t wanna mislead anyone or waste time and money.
So again I just got my truck back today and so far so good. I will post again later this week once I keep driving it. I’m also gonna put that PPE standard tune in it for a little extra power now the injectors are new and I got a fresh ecm. I should have it tomorrow in the mail. Read my posts carefully before throwing money at your truck. All situations are different and I’m just posting my experiences and situations and trying to help.