My SES light came on 2 days ago, if you don't mind letting us know what the dealership tells you, as I will most likely have to do the same thing...

 

*Both* banks running lean probably isn't an O2 sensor or even an exhaust problem. Smoke test your intake, most likely a vacuum leak somewhere. Would also help if you could drive around and log vitals with Cipher and post them up, to see the actual sensor readings and if you have some other issues with stuff like knock or cam phasing.

 

Well the saga continues. She has been to the dealer 3 times now.

First visit:
1) Said it was running lean. Expected to find leaky injectors so they pulled off the intake. Injectors were not leaking. Then said they were clogged and performed a fuel cleaning. Also had them replaced the plugs while in there....$664. Light came back on the next day.

2) Second visit they replaced right rear O2 sensor and said it took care of the SES light. They drove it enough that it passed state inspection. Wanted $250 for the sensor, I told them that was some crazy profit as I could get the same OEM sensor for $146 online. With no challenge or attitude ended up just charging for the inspection. Light came back after a day.

3) This time they "reprogrammed" the computer and drove it a lot of miles. No charge. Light came back on the next day.

Going back on Monday....

Fustrating, but they are giving us a loaner and I have to say the service advisor is very good. I am also happy they are willing to work with the car since it doen't have OEM O2 sensors in there. If I did it again - I should have just bought OEM from one of the dealer discount sites. But I think the dealer would be blaming the sensors if they thought it was them? Who knows at this point.

Anyway I will post the conclusion when we finally get one....

 

I got my car tune last month and the codes have not come back, Rob from Z Car Garage told me the car was running very lean. I don't know if this helps you since you are mostly stock.

 

Tuning will probably fix it but I'd still rule out the obvious. Like I said I doubt it's exhaust related if both banks are the same.

Look for sources of vacuum leak with a smoke tester, even simple **** like a faulty PCV valve could cause lean condition in both banks.

Not sure if you tested the fuel pressure under load but you could have a clogged fuel sock or failing fuel pump, ect. Testing at idle or free revving isn't enough, it might only be dipping under heavy loads.

Ultimately you should take it to a competent Uprev certified Nissan performance shop. A couple pulls on the dyno with A/F and cipher logs and it should be very easy diagnosis. Don't waste any more money at the stealer throwing random parts at it.

 

It has been back to the dealer twice more.

The last time they found a crack in the catalytic converter. They said that it leaks if put under stress and that is triggering the SES light. They said the other side has a similar crack but is not leaking. They want $2400 to replace them both. Knowing there are other options I declined.

So will be looking at aftermarket cats to put in. Can anyone recommend? Want something legal in NC.

Also any chance the O2 extenders can "fix" something like this?

The good news was the SES code stayed off long enough that the dealer got the state inspection done (NC)...so I have time now before really needing to fix.

Thanks for all the replies.

 

dba... I have the same situation as you and also in NC. I also had a Z tube from COBB tuning... throwing 1283 and 1273 codes.

My first guess, is that I have a vacuum leak somewhere relating to the Z tube so I installed the stock air intake, reset the ECU and now still have the CEL light.

I have test pipes that I installed, drove for a year and no light. but lately have started to rattle, sounding loose.

This is driving me crazy!

 

I get the same error code: P1273.
I have a single Turbo setup though. I have checked for vacuum leaks but didn't think this was the problem.
I've been told it could be an exhaust leak near the O2 sensor.

My vacuum/boost gauge is at 22 in Hg at idle. Not necessarily a vacuum leak just needs to be tuned properly for the correct fuel pressure/air mix.

Do you have a vacuum/boost gauge you can use to help you find out if you have a vacuum leak?

 

I get the same error code: P1273.
I have a single Turbo setup though. I have checked for vacuum leaks but didn't think this was the problem.
I've been told it could be an exhaust leak near the O2 sensor.

My vacuum/boost gauge is at 22 in Hg at idle. Not necessarily a vacuum leak just needs to be tuned properly for the correct fuel pressure/air mix.

Do you have a vacuum/boost gauge you can use to help you find out if you have a vacuum leak?

 

what other mods are on the car?? i threw this code up until i got tuned and it fixed the problem.

from what i have read the bosch o2 sensors only take half the readings of the OEM denso sensors. where do you get gas and im assuming its premium as well?!? i wonder if the ethanol all these companies are using is screwing stuff up cause ive had mine pop on for a tank worth of gas then when i get gas again and drive it for about 40 miles it turns off. only happened twice in the past year

 

This saga continues. Had a little time since it did pass inspection.

Bought some 35k used catalytic converters from the forum and had them installed. Now we are looking at a P0037 code. This one points the bank 1 sensor 2.

I had already replaced all 4 O2 sensors, but maybe this one got nicked during the install at the shop? I have no clue at this point...

 

DBA4life... Hello! How did things turn out on this p1273 code - sensor - cat conv saga for you?? I just thru same code on my total stock g35x. Hoping to hear a nice final, soft landing for you. Would you let me know please?? tks man!

 

Anyone have any fixes for the dreaded p1273 after hfc's?

 

Who tuned your car? No one wants to tune my car with 1273 and 1283.

 

Seymore4 tuned my car and got the light off