Ok I have an 04 5at coupe with 135000 miles all highway(like it matters).
I used royal purple and pushed it to about 6000 miles before I changed it. I normally change my oil 4500-5000 with it being only highway miles. When I changed the oil it was low but it was mostly sludge. There was no antifreeze in it( I know what that looks like thanks to my old accord) I used Pennzoil Platinum 5w-30 this time. I am hearing to many bad things about RP. Anyways after the oil change, I started it and I had white smoke for about 10 second and the car sounded like it wasnt running on all 6. It stalled once but fired right back up. I drove it around the block a few times and everytime I came to a stop it was running ruff but it slowly got better until it was gone. Drove it 150 miles yesterday with NO problems. It sat up for the day today until an hour ago, I started it and white smoke and running a little ruff but no where near as bad the first time. I am thinking it is my head gaskets. I wanted to see if the majority agrees or not. Thanks