 1998 Mustang V6 - Rough idle after start then goes away
I am having a issue where I will crank up my car, it will fire up fine and as the rpms are dropping from the initial start it drops to probably around 400rpm and sounds like it had some radical cams. If I rev the engine for a few seconds it will idle back around 900 or whatever it is normally. It doesn't always seem to do it, I just had it happen and it was after I returned home from about a 30 mile drive and came back out about 15 minutes later because I forgot something and it did it. The car has a little over 77k miles on it so not sure. Just wondering what I should start checking or replacing. Btw, it is showing no codes. | 
