just because it gives you a code for the oxygen sensor does not mean to always replace it.... you have to look into the problem... i recommend connecting your car to a real scanner either from the dealership, or a snap on unit . this way you can see live data, and see wuts creating the sensor to throw the mil, wut engine mods do u have, a very common prob for a dtc to set like this is usually the coolant temp sensor, buuut thats not always the case, has the car ever overheated ????

 

You mentioned to me that your friend removed the intake manifold and injectors while working on your car... I bet your problem is related to this. There is likely an air/vacuum leak around the intake manifold, fuel injector, etc. Again, as mentioned a couple of times now, buy a cheap cable for a laptop and run some diagnostics or have a shop run diagnostics... obviously the o2 sensor is not your issue.

 

Yea. Except my friend is being lazy on me right now and he isnt doing it yet. Shouldnt be to hard trying to find it huh.

 

No mods to it yet and never overheated. I bought it to the dealer already and they gave me that code.

 

Buying a diagnostic cable that you can connect to a laptop will yield a lot more info than just a code. I used the code combined with o2 sensor voltage readings and other information to track down the issue with my car. If you don't have the mechanical know-how to check for air leaks around the manifold and injector seals, kick your friend into motion or take the car to a mechanic to troubleshoot.

 

I also work at a shop part-time, used to be full time, and I've never had a problem with Bosch on any car.

 

Ok Ill try to ask him and see what he can do. Thanks.

 

no mods n no work ever done to the vehicle... ok 2 check for vac leaks either get a can of brake cleaner and spray on multple vac hoses gaskets etc, if car stumbles theres your leak, or get propane n do the same as above, if no stumbling, either theres no leak or the leak is waaaay to small, which honestly wont throw that o2 code. and check to see if the air intake boot is loose or not on correctly, this can cause it as well, 100% its not your o2 sensor,,,, and really i would just take it to a reputable shop n jus get it done right, stop throwin parts on it. let someone diagnose the problem with a real diagnostic scanner!!! not a pep boys one

 

so have code p2a03 looking into the problem I have hooked up a ob2 scanner, it is reading that bank 1 and bank 2 both sensor 1 are not getting any voltage. Not going to lie I was in the ditch the other day, was not bad but the code came on after 100k after the accident. So I figured it hit some wiring but it all seems to check out. Im going to have to pull my headers just to examine for cracks I guess... Anyone else have other options? all wires are connected and the sensors dont seem to have taken damage. 08 350z

 

Check the fuse?

 

I demolished my o2 sensor a few weeks back. ordered a new one. put it in and am getting more codes than I did with the o2 sensor out. I'm pretty sure its the fuse from what I have been reading. I just can not find which fuse it is..

I literally searched everything. Can not find the loaction or spot for the o2 sensor heater fuse.

 

what if you do some how connect the wrong sensor to the wrong place, what will happen?

 

You'll get bad readings until you install the right part. Long-term, it can potentially foul your cat.

 

okay im in need of help ive been having this problem for a while but i still cant figure out why im having a p300 code thrown after ive changed the coilpacks and o2 sensors.now im seeing that the voltage drops to 0.00 on all o2 sensors is that even supposed to happen?

 

No, you should not be getting a constant 0 volt reading. You can try an open/closed loop test. Check the PIDs for RPM, AFR, TPS, lambdas and all 02 sensor voltages. You only need to post a couple scan results from open loop and closed (it's better if you can post a video or more than just half second intervals.)

Before you do anything else though, make sure all your 02 sensor connections are solid.

I'm assuming you went aftermarket (non-OEM) with all your parts, right?

 

no there all oem well should be that's how I got the car

 

How many miles are on the car? Also, how many miles were on it when you purchased it?

 

I got the car with about 156,000 now there's 162,000
ive done an engine swap with the same vq35de because the last owner cracked a head gasket.

 

Did the problem only surface after the engine swap? Did you only swap the head and the block or did all the electronics from the (presumably) wrecked car the replacement engine came out of get transferred over as well? This is all info you should have divulged when you made your first post. It sounds like your issues could run a lot deeper than just a bad 02 sensor.

 

The problem was there since I had the old engine. I swapped the entire engine out and kept the wiring harness because the enigine was an automatic that I swapped too. I believe it's the wiring harness that's bad somewhere