I installed Kooks 1 7/8 headers and catless xpipe on my car last weekend. The car also has a mamo LSA TB and an Air Raid with a Green Filter. When i did the install I installed a wideband as well in the passenger side 02 bung of the x pipe. I drive the are after the install to make sure it was good to go and it almost stalled when I backed it into the driveway after the test drive. I figured it was due to the stock tune so I didn't think it was a big deal. I didn't drive it for a few days, until i had it tuned. Once it's over ~1,000 rpm it runs fine. The idle is a little rough (running BR7EF plugs now) and my fuel trims go straight to 28% once i let off the gas the go back to normal. It's not that noticable if your traveling at a decent rate of speed, but when I'm in stop and go traffic or backing up (especially on an incline) the car almost dies. It will stall if i don't give it a little more gas to keep it running. I've checked all the plug wires and they are seated on the coils and plugs (OEM wires with heat shields). What else could cause this?