High af readings on a and c

[Scubaru03]

I have a 2005 obxt. Stage 2 catless up and dp tuned by Brentuning. I recently noticed my mpg dropping from 22mpg to 20mpg. Notice my af learning a was at +15% and b,c,d were all within 0-3%. I check all my vacuum lines and everything is connected. So I ordered a perrin inlet suspecting my stock one was torn. I removed my stock one and can't find a tear in it. I still installed the perrin because the rubber was all gummy at turbo connection. Now my af learning a is at 15 still and c is at 9. The car is not throwing any codes and runs smooth. I still hit 18psi and vac sits at 9.8 at idle. Is it possible my pre turbo o2 sensor is failing but not throwing a code? Any thoughts?

Thanks

[discojon]

Definitely a vac leak. Check around and under the manifold. Log Afr and see what's its doing to check.

 

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[Scubaru03]

Found my leak with a pressure test. Was at the purge control valve solenoid. When I tried to pull the line off the nipple snapped clean off. A local guy from another forum has one from an 06 wrx. Does anyone know if they are the same part? Number 4 on the diagramhttp://img.tapatalk.com/d/14/05/19/jumyryny.jpg

[xt2005bonbon]

Can't answer your question, sorry. But I think you should post a larger version of your diagram. It is a bit hard to read. But very helpful diagram nonetheless.

[Scubaru03]

I got the diagram from a thread on here not sure how to resize it. I found my leak. Was the intake manifold gaskets. http://img.tapatalk.com/d/14/05/25/pabupazy.jpg