850 wagon n/a codes 171&103 assistance needed.

superfing · Post by **superfing** » 02 Jul 2014, 12:18

First let me say I have done due diligence before posting.
I originally had a 171 code and I ended up looking at the vacuum diagram and replacing elbow unit connecting to the maf sensor bc the hose was shot. While I had it apart I pulled the housing that contains the thermostat and put it in the freezer and watched it slowly move so I figured it was good.
Had the code removed and went camping 5 hours away. The 171 came back on the way but it has never affected driving. During the trip the car started stuttering bumping like I'm not getting gas but it doesn't die and made the trip home.
I figured o2 sensor as the maf is 3 months old factory part. Cleared codes again, they came back right away. Help?!

superfing · Post by **superfing** » 02 Jul 2014, 12:29

I also replaced the the hose in the 2nd picture with a generic hose that seemed to be slightly larger in diameter but it tightened down nicely. And I used generic hose to attach that vacuum to both sides of the airbox. Would hose diameter inside the hose cause any issues?

Post by **mecheng** » 02 Jul 2014, 12:55

Did you search OBD Codes for P0103?

superfing · Post by **superfing** » 02 Jul 2014, 13:45

Of course. It seems to point to maf sensor at least that's how I read it.

superfing · Post by **superfing** » 02 Jul 2014, 18:12

Anybody?

Post by **mecheng** » 03 Jul 2014, 06:35

Yes, start with the MAF sensor, they have finite lives. Use a OEM Bosch one. Reset codes and report back.

superfing · Post by **superfing** » 11 Jul 2014, 16:45

Maf sensor replaced again with Bosch part. Car runs and idles perfectly. I wouldn't know anything is wrong. Except the cel is still on after reset. Just p0171. Ideas ?

Post by **mecheng** » 11 Jul 2014, 20:00

It could be: vacuum leak, sticking injector, exhaust leak before first o2 sensor, o2 sensor itself, plugged Pcv

Check those things first and clean the front 02 sensor