Running Rich with a po172 code

[Demona_subie09]

Hello my fellow subaru brothers I am running into a issue that me and my tuner are kind of stumped. So I am stuck with a problem with my car throwing massive amounts of fuel at idle but it's not all the time it seems like it is when it's really hot and humid. I had this problems before and I had some misfires but after new spark plugs new coil packs and front o2 sensor I thought I beat the problem but about a week ago it came back idle afr will drop close to 12.0 I check for injector leaks and haven't find anything if any of you can help I would greatly appreciate I will list mod list below

Hks equal length headers
Perrin up pipe
Invidia downpipe
Invidia n1 catback
Turbo xs fmic
Forged bov
Turbosmart wastegate actuator
Iag tgv and egr deltes
Dtl coil packs



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[Batmobile_Engage]

I'm super busy right now and can't devote much time to this, but I want to mention a couple things...

- I imagine you've looked at what the MAF is putting out. If not, take a look and see if your tuner finds it to be acceptable.
- Remove and clean the MAF, very carefully. Weird shit happens when it isn't reading correctly.

Anyways, back to work for me...

Any other ideas [MENTION=9]HolyCrapItsFast[/MENTION] [MENTION=652]Grinder34[/MENTION] [MENTION=1172]Alin[/MENTION] ?

 

[Alin]

Just realized you said FMIC. What intake do you have? Clean the filter while you're at it.

A quick google search shows that PO172 is:

Possible causes:

Faulty front heated oxygen sensor
Ignition misfiring
Faulty fuel injectors
Exhaust gas leaks
Incorrect fuel pressure
Faulty Mass Air Flow (MAF) sensor

Start with the MAF like [MENTION=662]Batmobile_Engage[/MENTION] suggested. :tup:

[MENTION=1868]Boogieman98[/MENTION] [MENTION=5388]Raven32[/MENTION] [MENTION=1]IGOTASTi[/MENTION] [MENTION=600]black bandit[/MENTION]

 

[Grinder34]

Hmmm, its only at idle? Have you checked for any leaks? I know this sounds silly, but i'm wondering if there's some small leak/tear somewhere that gets covered up as the engine torques and physically moves. Dunno if that's plausible, but I dont have any other great ideas.

 

[Batmobile_Engage]

Hmmm, its only at idle? Have you checked for any leaks? I know this sounds silly, but i'm wondering if there's some small leak/tear somewhere that gets covered up as the engine torques and physically moves. Dunno if that's plausible, but I dont have any other great ideas.

Stranger things have happened...

 

[HolyCrapItsFast]

Does your tuner have a wide band AFR gauge he can hook up. You need to compare actual AFR to the front O2 reading from the cars sensor. If they differ then the O2 sensor is bad. As batmobile said, a dirty MAF can cause this also as well as the mentioned dirty air cleaner.

Also if this is happening while tuning have your tuner take a look at MAF scaling right around the idle region and check to see if any adjacent cells contain extreme values. If you have bigger injectors installed look at minimum injector pulse width. It will need to be reduced.

If he is willing to do so, post a logof idle and off idle.

 

[Grinder34]

[MENTION=6031]Demona_subie09[/MENTION] Ever get this resolved?

 

[Demona_subie09]

[MENTION=6031]Demona_subie09[/MENTION] Ever get this resolved?

We determined that the car is not reading Ethanol content of the fuel for some reason so I trying to figure why or what can cause that issue hasn't been doing the running rich at idle recently but I need to solve this issue

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