JPsTc

Ok, so I installed my boost gauge and I accidently turned on the car without plugging the maf sensor back in. The car instantly shut off and i threw a check engine light. We plugged in the OBD II reader, there were three codes all for the maf sensor so we plugged it back in and reset the codes.

About 50 miles later the Check engine light came on again, I thought i was odd so i reset the battery and went along my buisness. About another 60 miles or so the light poped on again! So this time I went to a friends house we read the code and got P0139 i believe. Something about the 2nd o2 sensor reacting slowly or something like that. We got underneath the car, made sure the o2 sensor was plugged in tightly and the cel fix ( I have a header) was on tight. Everything was fine. We reset it again.

Then it came on once again, only this time after driving with it several miles it turned off on its own. Thought all was good in the world until we red it to make sure it was the same code, it was reset it and now it has come back on once again....

Im assuming that I have to buy a new o2 sensor and my options are to order it ftom trdsparks for about $100 or this site has a few to choose from.

Does anyone know which one I can purchase to use for the o2 sensor on the spipe? Heres the site :

http://www.autopartswarehouse.com/se...94967015+11921

Scott8

iTrader: (1)

I have had a header and the CEL fix, and my CEL light will jump on, then off at random.

I would test your o2 sensors before buying new ones

TcPrincess

make sure you don't have any exhaust leaks before you go buy a new sensor. you can also test it out.

Mid_Life_tC-risis

Make sure you know the exact code first, then research it in the Tech section before you buy parts (that might not need replacing after all) ...

JPsTc

^Yea im positive it was the P0139 Here is what is says :

http://www.obd-codes.com/trouble_cod...1-sensor-2.php

KrazyAzianTC

how do you test the o2 sensor?

Mid_Life_tC-risis

hmmmm ... P0139 is not listed in the Diagnostics in the Repair manual:

https://www.scionlife.com/tech/manual/?manual=tc05_0229

??? List jumps from P0138 to P0171. I know most of those codes are for Bank 2 which we don't have ...

Anyway you can test your heated O2 sensor with a multimeter:

https://www.scionlife.com/tech/manual/?manual=tc05_1348