CEL question

I left my car at the airport the last two weeks and on the way home from Charlotte I threw a CEL. P0171 system too lean (bank 1). The car was running great before I left. I have a few questions about this.

Could this CEL be from just letting the car sit too long?

Is there an inexpensive way to diagnose the problem? I know the CEL can mean a few things, but not sure of them all, O2 sensor, fuel system?

Do you think this requires a Subaru specific mechanic?

Thanks for the help and any other insight you may have.
Tom

 

Others more knowledgeable can chime in, but it was my understanding that this CEL was most likely the front O2 sensor. I think it can also be MAF related.

 

I hope that is all. I don't mind replacing either of those parts myself even if they are a little pricey.

 

i think this has been covered a few times on here, clear the code and see if it comes back.
i had this pop up after my vf30 swap, but hasnt come back since
but i got plenty of air pump failure CELs :grr:

 

It is possible that it came up from sitting, condensation building up on the MAF or the O2, lots of possibilities. But yeah as others have said reset it, give it some time driving and see what happens.

 

Thanks guys, now to find a shop that will reset it, since Advanced doesn't do it anymore.

 

disconnect battery, press brake pedal, reconnect battery


if done quickly you won't loose your radio presets

 

It went off without having to do anything. I guess a certain amount of start-ups will do it also.

 

i cleaned my MAF with a CRC can and cleared the code. Mine hasn't come back yet...

 

....and now it has. time to check the codes when i get home...

 

I just cleaned my MAF the other day as prescribed. The light has been coming on what seems to be on longer trips. It never comes on during my short 15 min. commute to work. After a few days it will go back off and then back on when I shoot back up to the mountains. I guess I will have to look at the O2 sensor possibly.