fitted a new 02 sensor now getting P0172 – O2 Sensor Bank 1; System Too Rich could this because of the dv i have a forge dv but i fitted the weakest spring my car is mapped shell i fitted the yellow spring or am i fishing with out a rod here 

 

 

It should be yellow I don't think green was strong enough for mine. Or you can try shimming the green up so its in between the 2. However, whether this is related to your code I'm not sure. Never happened to me with the green spring Forge. I've put the standard one back on now anyway, can't be arsed tuning it to be fair.

For info - http://wiki.ross-tech.com/wiki/index.php/16556/P0172/000370

 

What condition are your vacuum pipes and dipstick tube in?.

Running too rich is nothing to with the DV. Split vacuum or oil breather pipe would be my first suspects.

Replaced breather pipes not long ago the only thing new is the O2 sensor and the dv but the code does say air leak maf or exhaust leak but the dv does chatter a bit on full boost

http://wiki.ross-tech.com/wiki/index.php/16556/P0172/000370

Have you replaced both mate or just the one?