Help with CEL error

[98blackspyder]

For the past couple of months my check engine light has been turning on. It even went away for a while but now it is back and is hurting gas milage and power of car. When i make a stop at a light or somewhere car idles very rough and even stalls at times. Condition gets worse if the AC is on. I took it to Autozone to get the check engine light test that they do and gave me the Fuel Trim Malfunction Bank 1 error. They gave me te following possibilities.

1. Mass Air Flow Sensor

2. O2 Sensor ( replaced 2 weeks ago)

3. Ignition misfire-repair

4. Fuel Injector Problem

Any suggestions of the problem? have any of you guys had a similar problem? My mods are injen intake with K&N filter, Greddy IC pipes with type-s bov, full 3 inch greddy exhaust.

 

[freshlane]

They told you those are the possibilities, but what CELs were on?

 

[98blackspyder]

CEL P0170. Sorry about that

 

[ekanddsm]

What code did it pull up? Pxxxx? What kind of freeze frame data did it give?
I'd hate to give the same song, but do you have a boost leak?

 

[ekanddsm]

No freeze frame data?

 

[donmagicjuan]

Based on the limited information available, I would proceed with your list of possibilities in the following order:

1. O2 sensor - it's always best to start with the thing you most recently touched. Also the most obvious cause of a fuel trim CEL.

2. Mass airflow signal - you aren't by chance venting your BOV, are you?

3. Fuel injectors - they're pretty simple to remove and test.

4. Ignition system - not likely without an accompanying CEL code.

 

[ekanddsm]

How much boost are you running? and did it set the light during the day or at night?

 

[98blackspyder]

im running sock boost. not venting BOV at all. I did boost leak test and couldnt hear anything leaking. as far as boost when i try to launch it it is ssslllllooooowwww! then it picks up to about 10psi and quickly drops to about 5 or 7