Code popped back up after d/c battery
 

I unhooked my Negative battery to clean my Throttle body and to root around my car trying to figure out my overboost source. I had it D/C for a day. I put the car back together and everything seems good. Car felt like it should driving around. I'm still overboosting to like 8psi with a 5.5 lb spring but anyhoo.

My problem is that a code popped up again. (I guess I drove her 200miles before the code popped as i drove home from work). I had deleted this code like 7,000 miles ago and things were good. My car started up fine and no stumble. No need to blip the throttle or anything for the 7,000 miles. The car drove fine when the code popped up. Yesturday, I tried a cold start and she stumbled a little so I gave her some gas and she turned right over no problem. Just right now, I started her up to data log and she started no problem. No stumble to blip of gas needed. Granted it's hot as heck outside right now.

http://i226.photobucket.com/albums/d...pssgiun8pp.jpg


So I tuned on the logging thing and this is what I got.
http://i226.photobucket.com/albums/d...pszvih2ozr.jpg

Here are a few snaps of the data log

http://i226.photobucket.com/albums/d...psahumpl72.jpg

http://i226.photobucket.com/albums/d...psfzcopird.jpg

I didn't get a chance to recheck all my rubber connections and clamps yet but I will in a sec. I did go over to make sure all and everything was good and tight when I put the car back together 200 miles ago.

What do you guys/gals think is wrong and what I should do?

YzGyz

Bump Bump. My local shop guy said to get a new bank 1 sensor 1 sensor (front passenger size). I did a little research looking to see which sensor brand is good or bad. I didn't ask my shop guy which sensor brand because I forgot to and he ran out the door on errands as I left. DOH!!!

Some reviews say get the cheapest ones because they are just 1 simple wire reading and nothing complected. Other read get AC Delco or Denso (Delphi) because they had trouble with everythign else. Then there are those that say Botch because that's what they use and it has lasted years.

Anyhoo, which brand O2 sensor should I get? Where did you buy them at?

YzGyz

I've never seen the inside of an automotive O2 sensor, but according to Wikipedia, they seem to be the same type sensors that I worked with at a hazmat incinerator to measure O2 in the incinerator exhaust. If they really are similar, then they are a little more complicated than "just 1 simple wire." They are simple (just a ceramic core with Pt coating on both sides), but building one so it works right is not. All that to preface recommending getting one of the three brands you mentioned (or other high-quality brand) and not cheap out. ;)

Isn't OEM Denso?

Either way enjoy that job. It sucks cuz you can barely get be socket on it and you are limited to a very small angle to ratchet. Straight from the top is the best position I found.

I also recommend heat wrapping the new sensor before you put it in. It's really close to the turbo.

P2A00 is not a bad sensor. Generally this code is caused by an air leak somewhere between the MAF and the primary O2 sensor. If the O2 sensor was actually bad you'd have about 2-3 other codes along with it.

If you still end up replacing the sensor make sure you get the correct one as somewhere around 2010-2011 Nissan changed the connector on the sensor.

fwiw the primary O2 sensor on our Z's have 4 wires. They are also very sensitive to hard vibration (impact guns). O2 sensors of the past may have been cheap and simple but the ones on our cars are definitely not.