Garrett_klenke

New to the forums, so hello to everyone hopefully y'all can offer some advice. I've had the Z for 6 months now (2003 Touring) and have had no issues out of it until yesterday when the SES light came on I checked the codes and its p0057 and p0327. Cleared the codes, drove around for 30 minutes and it didnt come back on until I was sitting idle at a light for 5 minutes, the drivers side O2 sensor is brand new as when I first got it i had hit a turtle and luckily that's all it broke off but that was several weeks ago could it still be an issue with the wiring for that O2 sensor? And is it possible for that to trip the KS code too? I'm just at a loss any help would be great.

zakmartin

Did you replace the broken O2 sensor with an OEM or aftermarket part? Have you looked at the voltages coming out of Bank 2 Sensor 2 using a live scan tool in open and closed loop?

Obviously, the best way to tell if you have a bad harness is to get under the car and have a look at it for physical damage and then run the live scan to see if you're getting a correct reading. Don't discount that when the turtle bounced around under your car, it could have hammered the catalytic converter and essentially destroyed it. An infrared thermometer pointed at the exhaust pre and post-cat will give you an idea if the cat's fried. While the engine is at temperature and running, the reading should be hotter on the back end of the cat than it is at the intake side.

Regarding the knock sensor, that could be totally unrelated to the turtle. Considering your car is a 2003, you can basically expect sensors to start going bad on you. Use the information in the FSM if you want to bench test the knock sensor (before replacing it with an OEM part.) Fair warning: on the 350Z, the knock sensor can be a bit of a pain to get to. (click for link)

P.S. - Next time you post a help request, be sure to include the mileage on your car and a list of any engine mods.

Garrett_klenke

Forgot to mention that the exhaust is aftermarket and the second O2 sensors are infront of the Cats it has a full motordyne exhaust, headers to the tips. Could that be the issue? That I need to install o2 sensor riser/non fouler and as far as the KS I have read that the harness for the knock sensor is usually the cause more than the knock sensor itself. Does anyone know a place to order the harness? Ive done a full motor rebuild on a Chevy 350 so I'm not worried about difficulty of install. Just any major problem spots that anyone has had issues with while doing a replacement? Any suggestions?

zakmartin

You can get the parts at your local dealership or save a few bucks and get them online from Courtesy Nissan or one of the other sponsored vendors on this site. As for the aftermarket exhaust advice, I'll leave that one for people who've done the mods. My '08 is still pretty much factory stock from front to back.

Garrett_klenke

Thanks for the advice

Garrett_klenke

I had reset the SES light using the pedal trick to get it to read out the codes and clear them, and they were gone until I was sitting in traffic today and it popped back up, I didnt notice any difference in they way it was driving though, any help would be great.