Ford Focus Zetev SE 1.4 2001 (Y) - Code P0172 system to rich bank 1 #Archived Message
Posted by Shaun Dale on July 16, 2007, 1:53 pm
This one's so odd I thought I'd share it with you One fault code P0172 system too rich bank 1. Engine has a lumpy/erratic idle. MIL on (obviously). Performance seems a little flat but not unduly so. Listening under the bonnet, particularly with the intake hose off the airbox it sounds like someone playing bongos in the plenum chamber.The intake hiss is not constant, it comes and goes and you can hear the soft popping noise. Manifold vacuum is poor and erratic 36-41kPa. I would think the system is going rich because of the poor vacuum. The question is what is causing the problem? My thoughts are blocked cat, faulty egr valve, sticky valve or an airleak. The engine does sound a little lame on start up but settles onto a lumpy four.