Subaru Outback Forums banner

1 - 5 of 5 Posts

·
Registered
Joined
·
14 Posts
Discussion Starter #1
My engine was throwing a p0171 code. Mechanic told me both a/f sensors are bad. He cleared the code too. So new a/f sensors in it and mileage seems to be fixed (since it was too lean the car ATE gas) but the car idles really rough and wants to stall when I come to a stop. I've only driven the car about two miles with the new sensors, so how long can I expect this low idle to last?
 

·
Registered
2018 2.5i Limited w/EyeSight
Joined
·
207 Posts
Can't speak exactly to the outback in this particular case, but I've the same thing done to other cars and it usually took a day or so to get back to acceptable and then quite a while to return all the way back to normal - usually a couple of weeks.
 

·
Registered
2001 VDC Wagon - White pearl - 302,000 km
Joined
·
466 Posts
My engine was throwing a p0171 code. Mechanic told me both a/f sensors are bad. He cleared the code too. So new a/f sensors in it and mileage seems to be fixed (since it was too lean the car ATE gas) but the car idles really rough and wants to stall when I come to a stop. I've only driven the car about two miles with the new sensors, so how long can I expect this low idle to last?
He may have pulled the battery or the ECM fuse, which returns the ECM to factory settings. The ECM needs time to "learn" how to run. Your near-stalling situation is most likely the ECM testing how low the idle control settings can go, before it stalls.
Should be back to normal after 3 or 4 full closed loop drive cycles.
 

·
Registered
1999 30th Anniversary Legacy Outback DOHC 2.5L 4EAT, 2008 Impreza WRX 2.5L 5MT, 2008 Impreza Wagon 2.5L 4EAT
Joined
·
1,224 Posts
is the check engine light off? Then it's probably relearning the idle.
 

·
Registered
03 H6 OBW & 06 WRX Sportwagon
Joined
·
17,619 Posts
depending on the engine, there can be a hose from the IACV that gets knocked loose under the intake tubing when work is done.
 
1 - 5 of 5 Posts
Top