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Discussion Starter #1
Car had thrown 171 codes about once a year since I bought it three years ago. They always go away by the hits cycle. But now Car is cam swapped with a rotofab, ls7 maf and solo catback. Car had the rear o2 sensors deleted with tune. Driving last night got a cel for both the listed codes. Cleared the code and got it again today on a quick trip. Popped the hood and noticed the air filter box to maf was actually loosed and flopping about. Is that enough to throw the codes listed??
 

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Typically no, lean is unmetered air making it into combustion. Post MAF leaks like vacuum leaks, intake gaskets, pcv leaks. Could also be a tune issue. If you have access to datalogging or a scan tool with fuel trim monitoring it would help a lot. Would want to know if it is lean all the time, while idling only, or while cruising. Helps determine potential fault areas.

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Typically no, lean is unmetered air making it into combustion. Post MAF leaks like vacuum leaks, intake gaskets, pcv leaks. Could also be a tune issue. If you have access to datalogging or a scan tool with fuel trim monitoring it would help a lot. Would want to know if it is lean all the time, while idling only, or while cruising. Helps determine potential fault areas.

Sent from my SM-G892A using Tapatalk
as I said that I just popped the hood to check again and it would seem like my catch can had a bit of a leak from the bottom as there’s was oil drips and it was slick...might this be the culprit?
 

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Pcv leaks can cause lean codes, definitely address it. I dont think it would be large enough if its only a drip. If you have some brakleen, while the car is running, spray/dust the brakleen around the leak and see if the engine RPMs increase.

If you want, post a couple pictures of the pcv lines, catch can setup and the passenger side of the throttle body where a few lines connect. They can pop off or leak as well.

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Pcv leaks can cause lean codes, definitely address it. I dont think it would be large enough if its only a drip. If you have some brakleen, while the car is running, spray/dust the brakleen around the leak and see if the engine RPMs increase.

If you want, post a couple pictures of the pcv lines, catch can setup and the passenger side of the throttle body where a few lines connect. They can pop off or leak as well.

Sent from my SM-G892A using Tapatalk
Sprayed her down and didn’t notice any fluctuation in the rpm. My scanner is pretty basic but for the little bit I sat at idle this morning it didn’t detect anything. I’ll probably take her around the block a few times to check again. I sealed the bottom of the catch can drain and double checked the hoses. All seem to be good.
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Hook up a scanner, set it for bank 1 short and long term % spray carb cleaner around all vac hoses intake etc, when values drop like crazy, thats your area of leak
 
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Hook up a scanner, set it for bank 1 short and long term % spray carb cleaner around all vac hoses intake etc, when values drop like crazy, thats your area of leak
Still couldn’t find the leaks. I’m beginning to think I fixed it with sealing the catch can. I remember reading now that a unsealed or vented catch can could send a code.
 
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