Prior to replacing the PCV valve and hose on my 2005 Escape Hybrid it took about 50 miles of driving for P0171 to pop back on after resetting. Now it happens almost immediately. Strange thing is it is running much better, more power and better MPG. I'm thinking that either I failed to hook something back up or there is yet another issue. Any thoughts would be appreciated. BTW, the PCV valve hose was wasted.