i had a low cat effieciency code left bank two. instead of buying a new o2 sensor, i bought some simms as i am planning on going with an ORY. i plugged them in and started the car..still SES light i thought if the problem was fixed it would go out? i even started the car like five times..still the same. i did not want to have to reset the computer as i know it takes a while to learn everthing again and i really wanted to go to the dyno today.. this suks do i just need to reset the pcm?
thanks matt

 

reset the pcm, wont hurt anything, take off the batt. for 20min. and try useing any electricals in the car to get rid of any excess juice

 

alright, i reset the pcm,drove around for about 30 minutes and BAM..same damn light,same damn code,left bank two low catayst..WTF i just put some simms on there whats going on? shouldnt it not ever throw this code with the simulators on there? if its relevant it never threw this code untill i mixed some 101 octane with some 93 to run my n20 ..both were unleaded pump gas though so i dont see any problems there,mixed'em half and half. only ran 10 gallons.. 5~ 101 and 5~ 93. have had my cats checked they're fine.. i dont know what else to do. the simms dont have to be put on in a certain way (one for left side or right side do they? surely not.
Help please,
matt

 

If you are still getting the problem even with sims, it maybe a wiring issue causing a false code.

 

It's either the o2 sensors before the cats or after the cats where you can not use sims. I don't remember. Your not changing out the wrong ones are you?

 

mine had the same problem, put the sims on and the code still poped-up! So I replaced the passenger side o2 (before the cat) and no more SES light! Pluse the scanner was telling me the same code, somtimes they like to play games