P1123 P1125

I pulled these codes out of my car today i know it has something to do with the intake sensors or something but i do have a k&n intake and fabspeed muffler bypass. Anyone else get these codes with there mod and is there a way to correct it without taking out the intake and exhaust??

 

these are the codes are emmissions related and indicate the lean mixture threshold being reached by the oxygen sensors on both sides of the engine. they usually indicate faulty O2 sensors though if both are showing it can also be MAF related which might tie in with your K&N mod.
ive heard alot of tales of MAF issues with filter swaps though not enough to make any comment.

i take it your CEL light is just on solid with these faults? if you can read the codes then i assume you can clear them too. i would clear it off and watch for them coming back. if they do quickly then theres an issue there that needs investigation. its not uncommon for CELs to be thrown once in a while related to these in my experience and all still be ok. if the cars sat for a while and then driven enthusiasticaly for instance it can happen.

you can always try and clean your MAF for good measure but like all things id take it as a warning and keep an eye out for it coming back.
you can always take it to a dealer to run diagnostics and see if your sensors need replacing if you want to be wary.

 

The codes mean that both banks of the engine are running rich at idle. The O2 sensor are not the problem but are simply reporting the facts. Muffler bypass can sometimes cause the engine to run rich at idle or on deceleration. Reset the CEL by disconnecting the battery for a few seconds. See if it comes back. What year is your car?

 

really, a muffler bypass can cause an engine to run rich?
are you sure in your statement that an O2 sensor cannot be the cause of a P1123 or P1125 error code? you might want to check this.
since you are getting both id suggest it was something else to blame however you could have damaged the O2 sensors doing the muffler swap.
usually when both throw up its MAF related....or the electrics taking a funny turn. the codes are just telling you that it couldnt make the mixture anymore lean and the range was still not within specification. its very possible that it can just throw out for second and trigger a code and everything is working fine.
just double check you didnt knock anything when fitting up the filter and mufflers, reset the light and then watch for anything amiss when you drive it

 

I didnt touch any of the sensors putting on the muffler bypass and the car is a 1999

 

i was just checking as its easy to spray duck oil or wd40 all over them if you spray the clamps for the exhaust to help free them.

 

If there was anything wrong with your O2 sensors you would get another code...not the ones you got. The sensors are not the problem but simply doing what they are supposed to do when they detect you are running rich.

 

I already had this error a couple of years ago. I resolved the issue by replacing the MAF. Must be the easiest DIY thing I've ever done. Trying to clean up the MAF before replacing it is certainly a good idea. If it doesn't work, should cost you about $250.

 

I had the same two codes - an MAF clean with some contact cleaner has seemed to solve the problem.