SAI codes (p0410 & p0412) & p0157 o2 low voltage
01-10-2008, 08:19 PM
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SAI codes (p0410 & p0412) & p0157 o2 low voltage I went in for Aircare (emissions testing) today and failed because these two codes and a p0157 (o2 sensor circuit voltage low on the passengers side rear o2).
My question is: If I where to remove the SAI system (and probably the AIR system too) and have the check engine light (which was not iluminated anyways) tuned out would I then pass the test? All they do is plug the car into a computer and cycle the ignition a fiew times to see what OBD2 has to say.
As far as p0157, o2 sensor circuit voltage low on the passengers side rear o2, I don't really know why this would happen. As far as I know the o2 sensors where replaced in August when I purchased the car. I believe I can get these (the rear o2 sensors) tuned out aswell?
EDIT: yes I read the stickies
My question is: If I where to remove the SAI system (and probably the AIR system too) and have the check engine light (which was not iluminated anyways) tuned out would I then pass the test? All they do is plug the car into a computer and cycle the ignition a fiew times to see what OBD2 has to say.
As far as p0157, o2 sensor circuit voltage low on the passengers side rear o2, I don't really know why this would happen. As far as I know the o2 sensors where replaced in August when I purchased the car. I believe I can get these (the rear o2 sensors) tuned out aswell?
EDIT: yes I read the stickies
Last edited by Soul Crusher; 01-10-2008 at 08:19 PM. Reason: I read the stickies
01-11-2008, 11:13 AM
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To pass the inspection, you may need a tool that clears the memory of the codes. (depending on the regulations for the test - eliminating the check engine light might not be enough.) I'm sure there is a way you can do this manually, however I use this tool: http://www.autoenginuity.com/ to do it from my laptop. (I bought mine a long time ago and I'm sure there may be other better choices for a tool.)
I also had the P0157 code. It turned out to be a fouled mass air flow (MAF) sensor. I assume the engine was compensating for the bad air flow readings and was causing emissions that were out of bounds for the O2 system.
This is a common problem. GM published a TSB a while back blaming the MAF fouling on K&N-type air filters shedding their oil. K&N has research saying that the fouling is due to bad design and silicone leaking from the electronics and on to the sensing element. I don't have an opinion on who's right - either way the solution is simple - clean the MAF sensor.
There are now special cleaners for the job. I used a non-residue electrical contact cleaner and it worked fine. (There are also lots of resources on the web on how to do the job.) Theoretically, you should just have to spray the sensor contacts and be done with it. (I disassembled my sensor and also wiped it down with a Q-tip - but this requires EXTREME caution as one could easily damage the fragile element. New MAFs are not cheap!)
I also had the P0157 code. It turned out to be a fouled mass air flow (MAF) sensor. I assume the engine was compensating for the bad air flow readings and was causing emissions that were out of bounds for the O2 system.
This is a common problem. GM published a TSB a while back blaming the MAF fouling on K&N-type air filters shedding their oil. K&N has research saying that the fouling is due to bad design and silicone leaking from the electronics and on to the sensing element. I don't have an opinion on who's right - either way the solution is simple - clean the MAF sensor.
There are now special cleaners for the job. I used a non-residue electrical contact cleaner and it worked fine. (There are also lots of resources on the web on how to do the job.) Theoretically, you should just have to spray the sensor contacts and be done with it. (I disassembled my sensor and also wiped it down with a Q-tip - but this requires EXTREME caution as one could easily damage the fragile element. New MAFs are not cheap!)
01-11-2008, 05:49 PM
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yea i had the same code except mine was PO131 which is low voltage bank 1 sensor 1, first of all when the sensor gets low voltage that means there is not enough fuel, your running lean! when it get high voltage that means your running rich!! first try not to drive your car because since your running lean your computer is making the injectors dump a bunch of fuel so that fuel will clog the cats (same reason my cats got clogged) the way i fixed my problem is i found a open wire on the o2 sensor wiring to the computer then i repaired it, and then i also replaced my 02 sensor! replacing my 02 sensor fixed my problem! i had even recently bought the o2 sensor it was on the car for 3 weeks and turned out it was a factory defect! the new o2 fixed the problem! goodluck and let me kno if u need help
