here is my situation.
my car has 7,800 miles on it and has gt35r running 100octane all the time, never run leaded gas.

it got tuned with safcII and run fine since last week.
I changed from safcII to XEDE, and then my car start to idle so bad and running bad around town.

Then my tuner scan the code and it turn out to be my front o2 sensor gone bad.

now that u know the o2 sensor will cost me like $300, So I don't want to go wrong with my money.

is this scan code can be wrong?
and now I am so worry because normally the o2 sensor and last for awhile or this is just normal?.

thank you

 

hmm maybe your gas was leaded.. that is really the only way it would go out really quick... but other than that.. u must have a check engine light on correct...? so it would be you o2 senor then.. I would say just replace it and see what happens....

 

I have seen this before with running race gas. Front sensor needing to be replaced.
You can try removing it and soaking it in parts cleaner for a little while to get the white gunk off the o2 sensor.

 

yes, I have the check engine light.

If it need to be replace then it is ok.
I just worry about the xede because before I ran safcII never have this problem.
then put the xede on the car and then it happen.
May be the o2 sensor just gone bad in the right place at the right time.

 

bump for more experien

 

what make you think your front o2 is bad ?? do you have an aftermarket o2 housing ? also have you log the o2 voltage at idle? what does your CEL code ??