I have a 2011 1.8 that started running rough yesterday. it has codes P0171 and P2270. after a search I figured out its lean fuel system and maybe an o2 sensor? I'm not sure though. Any help would be appreciated
It could be a vacuum leak, that will throw both codes. Do you have the capability to check your fuel trims? Your Short Term Fuel Trim should be close to 0% at idle. If you're getting 20% or more, you have a large vacuum leak and the fuel system is unable to compensate for the extra air, and the codes support that.
Check everything attached to the intake manifold. It may be something fell off, or it may be a damaged vacuum hose.
Well, those codes usually mean 1 of 2 things - too much air or not enough fuel. Since it's not throwing an individual cylinder code that would lead to a dirty fuel injector, it could be that your fuel pump is giving up the ghost. But that usually is more abrupt, as in works one day and not the next.
I would run the engine and listen for a whistle or sucking sound, if you haven't done that already.
Replacing the fuel pump requires dropping the tank, and it's an involved job that's best done on a lift, even though you can do it in your driveway - I changed mine a couple weeks ago. I upgraded to the non-eco pump so I can get 3 more gallons in my tank.
It *could* be bad gas. I've heard that too much ethanol can cause these problems, but I think our cars are able to adjust for that even though they're not rated "flex fuel" due to not having the right soft bits in the fuel system.
Aren't those the codes that are set when the PCV valve breaks? I think someone on this forum should be able to confirm that, or you might want to do a search on the PCV problem. If they are, you might want to check that first. A few people have posted simple tests to see if it is a PCV issue.
so today I can hear a air leak at what I assuming is the pcv valve. If I take the spark plug cover off I can put my finger over it. I guessing this isnt normal? Its sucking in and its quite noticeable now. Would a new valve cover fix this? I called the dealer but they were not any help