I have a 2003 G35 coupe thats auto. It is all stock, no mods whatsoever with 78,5xx mlies. A couple of weeks ago my service engine soon light came on and I had my buddy check the codes. Turns out that all four o2 sensors are bad. My question is, is it possible for another sensor, bad ground, bad cat, or anything else make the o2 sensors go bad or make the computer think the o2 sensors are bad? We have cleared the codes and they have come back. Has anyone had the same problem, any help would be great.

 

bump for information

 

What kind of OBD2 reader did your friend use to pull the codes? Most readers pull generic codes and give you a general idea of what's wrong. The reader at the stealership pulls up a lot more specific info. Other places probably have the stealership reader and charge less for diagnostics.

The better OBD2 readers you can buy allow real time data-logging so you can trace exactly what conditions caused the CEL to come on.

 

x2 ^ Sounds like the OBD is just pulling a generic code. Pretty crazy that all four magically go. Try another reader, if not that sucks.

 

I have 3 o2 sensors that went bad all at once. I replaced the 2 in the cats with $60 bosch universal o2 sensors and I was still getting the same code (I have cypher). Took it the dealership and they said not to use the universal o2 sensors as they have been having problems with them on our cars. I priced them out and a new set (4) would cost you around $500. I have yet to replace mine, but I don't drive it anywhere.

hope this helps, and good luck

 

Try Seafoam first, might clean things up enough to not need to replace anything...

 

It's a bull****tttt

 

thats weird. Currently I have 2 30$ universal ones that work fine.....

 

What code did you get? If its for both banks running lean, you may want to check for a vacuum leak somewhere.

 

best bet in this case is to take it to a shop

it may just be one that is bad or it may not even been the O2 sensors, it maybe something before them.

 

i dont know if this helps out, but on my 4runner, my 02 sensors were showing up, yesterday my battery died and i replaced it, with the new battery the o2 sensor light doesnt show up anymore, i dont know if its resolved, but it was the first time i changed my 4runner battery since it was purchased in 03

 

Wow thank you all for your input. The scanner that was used is a Snap-on model, I do not recall the exact model. The scanner did read not one o2 sensor but all four... yes all four codes for each o2 sensor. I will check for vacuum leaks tomorrow. Does anyone have any other ideas?

 

What codes did the scanner pull? Copy them down and post them otherwise we can only give our best guesses.

 

I am currently having a similar issue. I got a P1031 and a P1148. I thought it might be the MAF but after cleaning that I still have the same codes pop back up.

AND DON'T USE SEAFOAM, THATS WHY I AM IN MY CURRENT SITUATION.


I was alway under the impression that you need to replace all O2 sensors when one goes out because 90% of the time the other one will go out soon after??? But I have never dealt with 4 O2 sensor.

 

Mine is showing the exact same thing.
all 4 both banks in alarm.

I hope I dont have to replace all 4 sensors that would really suck.

supposed to take it back to the dealership where I bought it to have it looked at for the door locks not working as well.
they said they would look at the o2's and the SES for me as I just got the car less than 3 weeks and the SES popped on the drive home.