I have this same Problem ! Only when the cars is cold tho after it warms up all this goes away... But im not on 550's or an ems.. I still have stock 370's and ecu.. I remember reading somewhere that this problem is DEF. a coolant temp sensor for the ecu that is bad... So i purchased a coolant temp sensor but havent gotten around to installing it yet...Ill let you guys know when i do
---------- Post added at 05:31 PM ---------- Previous post was at 05:29 PM ----------
Ive tried the other fixes but this one.. New o2 sensor, re-did all ecu caps, coil packs are ok last time i checked (Aout a month ago when i did my plugs).. so i just have to rule this out now..