Well got the new y-pipe in this morning and got it all back together. On initial start up, lots of stumbling like usual but it seemed to get better as I let it idle. It idled for a few minutes w/o stumble then I took it for a quick run around the block and still seemed fine. Put it back in driveway for 15 minutes and started again, no stumbling. Backed out of driveway and put it in D, as soon as I touched gas pedal I got some minor stumbling but it went away again. Do I need to reset anything after doing this. It seems much better but still lurking. Or will the computer correct itself after a few miles? I cleared all codes and will drive for a while to see if they come back.

On another note, doing this repair showed me that I have a valve cover/valve cover gasket issue and also while underneath I saw a few chunks of grease on lower control arm so it appears that my driver side boot is giving way. First one at 55K, second one just short of 65K.

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2010 Lexus RX350 still new
2003 BMW X5 3.0i w/sport package w/68K miles. (gone Thank God!)
2002 Dodge Ram 2500 4X4 cummins diesel w/198K miles, custom repo truck
2009 Scion tC w/46K miles
2007 Suzuki SV650 custom streetfighter
2000 Lexus GS400 w/165K miles