[Our03z4]

Just picked up my 2008 Z4 3.0si Coupe with the automatic trans. Unfortunately I've already begun noticing a loping issue when driving at 30-50mph. Almost like the ac kicking on and off heavily and about every 5 seconds. I have a roadster with the 5sp manual and have never had this issue before, just hope it's not the trans. Engine runs like silk at idle. It has been raining heavily so possibly a coil? I do also have a tpms light on that won't reset, not sure if it's related? Thanks for any help!!!