icestorm

i have about 105k on my tC and it started throwing DTC P0136 about a month ago after i changed oil (it was after 15K; yes i know i do not normally wait that long! i had also put in a can of BG44K and atleast gone two tanks before i got around changing the oil)

P0136 seems to be due to the downstream O2. i replaced it with the original one from trdsparks (denso; same part no).

after about 60 miles, the DTC came back on and the car still sounds loud.

any suggestions on what should i look for and in what order ? could it be an exhaust leak which would be a pain to find i think if that is the problem.

everything on my car is stock.

i would like to see if i can find the problem and fix it myself before taking it to my mechanic. :--)

icestorm

Here is a an article that i had found on possible causes for a loud engine (it includes bad o2 sensor):

https://www.yourmechanic.com/service...mal-inspection

Not sure if our tC has a code for each of these issues or if they could be covered under P0136.

icestorm

so quick update: the donut was missing on the front exhaust pipe ! after it was installed, the car sounded normal again which made me very happy :--) i will clear the code and i don't expect it to set again.

i was going through my my service records and realized that i had the front exhaust pipe replaced in 8/2014 with an aftermarket one and i am sure that the donut was still stock.

anyway, that it was not anything major.

hope this helps somebody.

samatman

Thanks for posting this. It's funny but most of the time an O2 sensor throws a code, it really isn't the sensor. I'm glad you found your air leak.