I have replaced all 4 o2 sensors with bosch from local Autozone. I have had to replace the (bank 1 sensor 1) 3 more times (so a total of 4 new o2 sensors). I forgot the exact code right now but the description was bank 1 sensor 1 running lean.

I have also replaced the mass air sensor with a rebuilt one from oriely, but I will be ordering the on roverparts. After changing the mass air I started getting tranny codes, for 4th gear incorrect ratio. Never had that problem until the new mass.

Any ideas what is messing up the bank 1 sensor 1. I also cleaned the connection with electrical cleaner and dryer.

 

MAF is perhaps the issue on the tranny codes. The engine computer sends a steam of data to the tranny, and the tranny computes what gear would be best. When input data pushes that out of a range of possibilities, the wierd ratio codes can result. Here's a page that shows you all the talk going on betwen the two computers.