what exactly does this mean? before my light came on i got normal gas mileage. the code was cleared then my gas mileage got really bad. now two days ago the light came back on with the same code and my gas mileage seems to be improving again. when the light came on the first time I had driven through a monster puddle and it felt like I got a ton of water up into my under-carriage. any ideas????

Downstream O2 sensor. It may have gotten water damage from the puddle, sometimes it will not completely damage it. You may need to replace just the O2 sensor. Worst case scenario, catalytic converter is shot. In that case, you will have to replace the catalytic converter.

which oxygen sensor? nissan says their are two sensors in bank 2 so i dont know which one to buy.

Downstream homie. 'Catalyst below threshold'. Downstream.

Here is a How to Remove/Install Rear O2 Sensor article for the 4th Gen. Your 01 may be just a touch different, but you can go to Phat G20 and download the 01 FSM in the downloads section and it will give you a more in depth picture.

My I30 tosses that code when I run the cheap gas (85 octane here)... A bottle of octane boost to the low grade fuel and I am back in business.--Mike

cool im gonna do it this weekend, i think the dealer is just being a dealer and giving me bull**** answers so i will go their and drop a ton of dough.

jltibbs wrote:Downstream homie. 'Catalyst below threshold'. Downstream.

Here is a How to Remove/Install Rear O2 Sensor article for the 4th Gen. Your 01 may be just a touch different, but you can go to Phat G20 and download the 01 FSM in the downloads section and it will give you a more in depth picture.

you guys are gonna want to kill me, but I have no idea how to find this part(i am a master at car audio but a complete novice with car parts). i have googled 01 I30 downstream o2 sensor and i cant find the part, only forums talking about it. if anyone could give me a link or if it has a specific name or part number i would greatly appreciate it.

Click pic to go to link.



Bosch Oxygen Sensor Part Number: 13374

Vehicle: 2001 INFINITI I30 Engine: V6 3.0 Liter FI OE Type; 4 Wire; Heated; Downstream Sensor; O2 sensor located in rear manifold/exhaust pipe.;Check / Replace Interval: 100,000 Miles

thank you very much.....

so it took me forever to get to this but I have been doing some research and some people say it is most likely my pre cat...if so what part is that? and where could I get a good deal on one???

Pre-cat is integrated into the exhaust manifold, so unfortunately the whole manifold must be replaced.

Your problem could be the pre-cat. But it also might be the other oxygen senor for that bank.