Lean engine codes p0171

[zackegle]

Hey guys I've been having an issue with my car running lean I've taken it to the dealer they swapped the o2 sensors, checked my maf and checked injectors they said it's just my bottom injectors being clogged and they just put injector cleaner in it and said to run it for 1k miles to clear the problem.. I find that bullshit I've had this issue for a while and brought it to them countlessly so now I'm here asking for your guys help! I have a oft so I run realtime logs as I drive everything seems fine when driving on throttle but when I come to a stop my afr jumps to 15-17 my idles drop from fuel being spit into the engine (ST fueltrim goes up to 14) and that's when my lean code shows up ive also noticed if i mash the brake while at a stop it will jump my afr and raise ST fueltrim.. idk if that's normal but does that sound like i have a leak some where on the vacuum lines on the brake system? Where would i most likely find the leak? Please help!!

[Tcoat]

Originally Posted by zackegle

Hey guys I've been having an issue with my car running lean I've taken it to the dealer they swapped the o2 sensors, checked my maf and checked injectors they said it's just my bottom injectors being clogged and they just put injector cleaner in it and said to run it for 1k miles to clear the problem.. I find that bullshit I've had this issue for a while and brought it to them countlessly so now I'm here asking for your guys help! I have a oft so I run realtime logs as I drive everything seems fine when driving on throttle but when I come to a stop my afr jumps to 15-17 my idles drop from fuel being spit into the engine (ST fueltrim goes up to 14) and that's when my lean code shows up ive also noticed if i mash the brake while at a stop it will jump my afr and raise ST fueltrim.. idk if that's normal but does that sound like i have a leak some where on the vacuum lines on the brake system? Where would i most likely find the leak? Please help!!

Any mods other than oft?

[zackegle]

Originally Posted by Tcoat

Any mods other than oft?

Just a invidia catback and suspension bits, no engine mods

[Tcoat]

Originally Posted by zackegle

Just a invidia catback and suspension bits, no engine mods

100% sure you have no exhaust leaks?

[nunonuna]

Originally Posted by Tcoat

Any mods other than oft?

According to his post in other thread, his car is stock other than oft stg1.

OP, This may not be the exact cause, but check PCV hose if that is loose somehow or leaking.

[guybo]

Originally Posted by zackegle

Hey guys I've been having an issue with my car running lean I've taken it to the dealer they swapped the o2 sensors, checked my maf and checked injectors they said it's just my bottom injectors being clogged and they just put injector cleaner in it and said to run it for 1k miles to clear the problem.. I find that bullshit I've had this issue for a while and brought it to them countlessly so now I'm here asking for your guys help! I have a oft so I run realtime logs as I drive everything seems fine when driving on throttle but when I come to a stop my afr jumps to 15-17 my idles drop from fuel being spit into the engine (ST fueltrim goes up to 14) and that's when my lean code shows up ive also noticed if i mash the brake while at a stop it will jump my afr and raise ST fueltrim.. idk if that's normal but does that sound like i have a leak some where on the vacuum lines on the brake system? Where would i most likely find the leak? Please help!!

The garage basically did everything wrong. Instead of diagnosing the issue they started swapping parts. If they changed the O2 sensors, checked the MAF (if they even know how to) and (the worst of all) put in fuel injector cleaner , they have demonstarted that they do not know how to diagnose a problem and don't understand how to interpret a CEL.

If you go back to the same garage, they will find a reason that it's your fault. Go to a better garage.

[zackegle]

Originally Posted by Tcoat

100% sure you have no exhaust leaks?

I checked the exhaust when I installed my catback but there is an odd smell under the car near the engine when idling so there has to be a leak some where I'll have a look at the headers again this weekend and I'll check the pcv line but is pushing the brake suppose to raise afr? That just sounds odd to me

[nunonuna]

Originally Posted by zackegle

I checked the exhaust when I installed my catback but there is an odd smell under the car near the engine when idling so there has to be a leak some where I'll have a look at the headers again this weekend and I'll check the pcv line but is pushing the brake suppose to raise afr? That just sounds odd to me

PCV = Positive crankcase ventilation.
I was referring to the hose that can be found behind the intake manifold runs down to PCV valve.

[zackegle]

Originally Posted by guybo

The garage basically did everything wrong. Instead of diagnosing the issue they started swapping parts. If they changed the O2 sensors, checked the MAF (if they even know how to) and (the worst of all) put in fuel injector cleaner , they have demonstarted that they do not know how to diagnose a problem and don't understand how to interpret a CEL.

If you go back to the same garage, they will find a reason that it's your fault. Go to a better garage.

We only have one Subaru in town sadly but I think there diagnosing abilities are bad as well because the 5 times I've brought the car to them they had another excuse or "diagnosis" for the issue that's whybim just trying to do it on my own now

[zackegle]

Originally Posted by nunonuna

PCV = Positive crankcase ventilation.
I was referring to the hose that can be found behind the intake manifold runs down to PCV valve.

I'll try to find that hose and see I'm not 100% sure where it is though is it visible from the top

[nunonuna]

Originally Posted by zackegle

I'll try to find that hose and see I'm not 100% sure where it is though is it visible from the top

Yeah it is visible from top. Take off plastic engine cover & you will see better.
There are two hoses connected to intake manifold. PCV hose is the one on passenger side. I had air leak from there and had same code, but this may not be the case for you tho.

나의 SM-G935V 의 Tapatalk에서 보냄

[Tcoat]

Originally Posted by zackegle

I checked the exhaust when I installed my catback but there is an odd smell under the car near the engine when idling so there has to be a leak some where I'll have a look at the headers again this weekend and I'll check the pcv line but is pushing the brake suppose to raise afr? That just sounds odd to me

One of the troubleshooting checks for that code is exhaust leaks.

[zackegle]

So I was checking my pcv valve line by disconnecting it and blowing smoke into it and I found a huge hole on this thing on the intake tubing would this be my issue and what does that container do? Can I block it off?

[zackegle]

Originally Posted by nunonuna

Yeah it is visible from top. Take off plastic engine cover & you will see better.
There are two hoses connected to intake manifold. PCV hose is the one on passenger side. I had air leak from there and had same code, but this may not be the case for you tho.

나의 SM-G935V 의 Tapatalk에서 보냄

I think I may have found the leak but that line seems fine