Advice on Multiple OBDII Codes on 2004 Non-SC V6

[ericlander]

I've searched through the forums quite a bit, and have found many links to be a lot of help with regards to the EVAP leaks, knock sensor and oxygen sensor. I have also seen a few threads where owners have discussed many of these codes displaying in conjunction with one another - so I'm hoping to get some thoughts both on the underlying cause(s) as well as a recommendation for fixing the issues.

My vehicle is a 2004 Nissan Xterra w/ the Non-SC V6 engine. The vehicle has 127,000 miles on it and has not had any known engine problems. Last fall I replaced the muffler, tailpipe and connecting pipe after the second cat - and that has been all the work required to date. I'm the first and only owner of the vehicle.

I just took the vehicle to the AutoZone where they ran an OBDII check on the vehicle. The following seven codes all came back:

P0138 - Heated Oxygen Sensor - Bank 1 Sensor 2 (HO2S12) Circuit High Voltage
P0152 - Air Fuel Ratio Sensor 1 Bank 2 Circuit High Voltage
P0158 - Heated Oxygen Sensor - Bank 2 Sensor 2 (HO2S22) Circuit High Voltage
P0328 - Knock Sensor - Circuit High Input
P0442 - EVAP Control System - Small Leak Detected
P0455 - EVAP Control System Gross Leak Detected
P1143 - Heated Oxygen Sensor - Bank 1 Sensor 1 (H02S11) Lean Shift Monitoring

I suspect that the issue is worse than a bad fuel cap, however, I will try to locate one immediately and give the vehicle a few days to see if that helps out at all.

What I'd like to do first is replace the fuel cap, pull the battery connections, and drive the vehicle (around town, nothing more than 20-30 miles total) and have the codes checked again to see if any of them have gone away.

In reading here on NICO, it seems that many things are possible, and I'd like to avoid the high price repair of the knock sensor if possible.

Any help, insight or advice on the situation would be greatly appreciated.

Thanks!

[Rev_D21]

First off, welcome to NICO. All 3.3l engines seem to be born with knock sensor codes. There is a relocation trick out there if you feel up to doing some rewiring. Otherwise the knock sensor has little effect on the non-SC 3.3l. I would start by clearing the codes as you stated to see which ones come back after a good test drive. A pdf version of the factory service manual can be found at www.nicoclub.com/FSM don't hesitate to download a copy as it is the bible when it comes to repairing these trucks.

[newbissan-tech]

Knock is a joke I disregard it every time I see it unless it turns the light on which it never does! The other need to be checked out and need to know how many trips since they were set? which no aftermarket scanner will tell you ( maybe snap on) and that info is important! Whether it's a current or stored code, they can be stored and not turning on the light,but the other active codes are what are turning the light on! there a lot more to it than just replacing all of the parts that are related to the codes! So I would suggest breaking down and going to a dealer, at least for a proper diag! You dont always have to have them do the work! But don't be afraid to ask questions either I actually prefer to consult with customers on their vehicle issues rather than a service writer, mainly because a lot gets lost in translation! Good luck with your quest!