these two codes seem to recur occasionally,weeks apart at most.

yesterday i had this occur whilst heading down dual carriage way,at round abouts,quick flick of and on of engine got moving again but not far,,pulled up on grass tot he side out the way,idling happy,press pedal nothing would happen,once in a while would work.

forced pedal re learn and made no difference still ahd same issue.

left car there over night got lift home, fetched it todaya nd it drove liek nothing was wrong,these two codes where there though P1221 P0171.

one i believe is the pentiometer but there are two? can these have bad connections and where does it connect exactly?

P0171 says system to lean bank one,can anyone clarify this? as in did one injector open to long when car went into limp mode?

yes this car is upf or sale as im moving on just wish to broaden my knowledge

may thanks

buttflap212

With too lean it can be lots of things, intake/vacuum leak or lambda sensors are a good start. Its not two seperate potentiometers, there are two wipers and two tracks for throttle.