I'm sorry to ask the question again, but when I got under the car, I only saw 3 o2 sensors, not 4 as shown in the picture below:



my car is 99 infiniti I30. I only saw 3 sensors:

please point out for me which one is the bank 1 sensor 2? thanks!

1. the one closest to muffler, with white cable




2, the one close to drive axle on passenger side.



3. the one under the driver side

Why did you start another thread? You have a thread asking for help with this issue already.

Fail -----

I went out and looked under my 99 I30 with Cali Emmisions. I have 4 sensors, One sensor can be seen by opening the hood in the exhaust manifold. My exhuast looks like the 01-03 diagram exhaust except I have a pre-cat in the front exhaust manifold. Your exhaust looks different than mine, I wonder if you have the federal exhaust.

sorry, I thought that question was already answered. already deleted.

you might be right, when I looked at the emission control tag, I didn't see califorlia, here is the tag:

is this a federal one?

It is the first picture, the one after the cat. This one only checks the cat, it has no bearing on performance.

I don't know from that picture. Look at the plate on the Passenger side metal plate on the firewall. The 2nd row of numbers will have either a V (cali) or U (federal) for the emissions code.

thanks! this one is easy to get to, but the wire seems to go through the floor to somewhere. I read a lot of posts, some say get a plug-and-play, but for this one, I guess the universal one may be the easiest way because you don't have to worry about wiring ??

this one? I didn't see a V, so i guess this is a federal ?

So how do I tell if my car is Cali or Fed spec?

Raise your hood. Look for a shiny metal identification tag fastened to the passenger side of firewall. The top row is the Vehicle Identification Number, starting with J. The second row is model information. The first five characters are BLHUL. The 12th character is the destination:

N = Canada
V = California
U = US, not California

Yours starts with CL...

Thanks for decoding

mine is a federal, got it!

Great thread goin on here.... I'm trying to find the O2 sensor locations in my 98 FSM, like the picture posted here, but dunno what page it's on????? Can anyone chime in?

Section FE.

Should in the FAQ's as well

Thanks, needed to know so i can put in the two new denso O2 sensors i bought.. no CEL, just doing maintenance, i wonder if there will be a noticeable difference in performance?

Just to be clear, bank 1 sensor 2 is between the 3-way cat and the rear exhaust tube assembly as shown on page FE-4 of the 1999 FSM????


I need to get my car inspected this month and the CEL just came on. Autozone pulled codes P0138 and P0139 which is this sensor (I hope).

Anyone?

Yes, that's the correct sensor. Get it replaced and be careful of tightening..

Those two codes are for the rear 02 sensor, which you can reach with your hand from under the driver's side door of your car. It's on the exhaust, you can't miss it.

Thanks for the help Trini and atriuum.

Paul

oh that sensor on the top behind the cat no fun on a 12 year old ny car i sheared off the entire hex with my o2 socket and i used alot of lube and a lot of heat oh well good think the sides of that pipe are flat, drill bit and tap worked awesome and now i have more tools! if anyone needs to know the tap size and drill bit send me a shout