Hey guys, I've never written on a forum before and Im really hoping i could get some insight on my situation. So I recently entered the world of Z's - I bought a 2006 350z, had about 120k miles on it. The car has a 1k RPM idle, the TCS OFF & SLIP light stay on always, previous owner cut off the secondary O2 sensors (Primaries are still on), it had a rear main and valve cover leak which i got fixed, and a slight power steering leak(planning on getting this fixed soon). I went over to a friends house to check the codes the car might have, it doesnt have a check engine light on but I still wanted to check it and to my (not) surprise it had a few codes I'll list them out

1. P0078 Exhaust Valve Control Solenoid Circuit Bank 1
2. P0084 Exhaust Valve control solenoid circuit Bank 2
3. P1078 Exhaust Variable Timing Control Position Sensor Bank 1
4. P1084 Exhaust valve Timing Control Position sensor (bank 2)
5. P0037 H02S Heater Control Circuit Low Bank 1 Sensor 2
6. P0057 H02S Heater Control Circuit Low Bank 2 Sensor 2
7. P0463 Fuel Level Sensor A Circuit High

So lol its kind of a messed up situation but its okay because i know little by little i can get this thing in better shape, it drives perfectly fine other than the high idle (1k rpm) and the random empty fuel indicator that slowly goes back up everytime i fuel up
but i guess the point of this post is to maybe get some insight on which one of these codes should i try to tackle first to maybe resolve this high idle. I appreciate any and all feedback, thanks guys

 

The high idle, TCS/SLIP lights, and P1078 and P1084 would point to the exhaust valve timing control sensors. Since you have an '06, you have the rev-up DE which has 4 of the magnetic sensors for the exhaust valve timing and camshaft position sensors (two angled and two straight).

The P0463 is the cause of the faulty fuel gauge readings. It could be a dirty or faulty fuel level sensor or I have seen where the soldered connections in the dash degrade.

My guess is P0037 and P0057 are likely due to the heated oxygen sensors being cut and disconnected.

I would start by reconnecting the O2 sensors and then what codes pop up after that since the majority of your codes seem to be exhaust-related.

 

wow, thank you alot for the response, i really appreciate the info, im going to go with your advice and try to get the o2 sensors back on there im not sure how much of a challenge its going to seeing how he cut off the secondary ones but man i really appreciate the help, it really gives me some insight on what direction i should head towards. 02 sensors and buy those 4 sensors you mentioned

 

one other thing it seems like the previous owner also did a cat delete, so should i still go ahead and get new o2 sensors replacing the ones they cut off?

 

I don't think you'll need to get all 4 new sensors. At least, I hope not. They're not cheap and the Z doesn't like aftermarket sensors. My thought was that the lack of the O2 sensors may be triggering the other exhaust-related faults.

If you don't have cats and you're running test pipes, you can get an O2 non fouler bung or extension in order to avoid tripping a CEL with the increase in air flow. If your test pipes don't have one, you might be able to take it to an exhaust shop and get some welded on. They usually have a J-shaped bend or some type of post coming off the test pipe. That's where the O2 sensors are mounted.

 

Im going to try to get under the car tomorrow and take a picture so you can see but im def going to check out that non fouler bung hopefully that takes care of some of the codes

 

as you can see they snipped it like this

 

Well, at least the previous owner left the OEM plugs in place. If you order new O2 sensors, they come with the pigtails to connect to those harnesses.



This is what the new O2 sensors will look like:



No real special tools are required to install these other than a socket that has a notch cut-out in one of the side to allow the wire to pass through.




You might need a spacer since your TPs don't look like they have a long extension welded on, but you might be ok.

 

Im about to order some stuff for the car do you recommend that i order only 1 exhaust valve timing control sensor for now and swap em out with each sensor to see which one could be the culprit or just order both since both banks came up

 

You could do that, but P1078 is for bank 1 and uses the angled sensor.

The P1084 is for bank 2 and uses a straight sensor.

If you wanted, you could try swapping the angled bank 1 EVT control sensor with the angled bank 2 camshaft position sensor to see if the problem follows the swap. A bad bank 2 camshaft position sensor will throw code P0345.

To test the straight bank 2 EVT control position sensor, you can swap that with the straight bank 1 camshaft position sensor. The code for a bad bank 1 camshaft position sensor is P0340.

So, in other words, you can't just buy one sensor and swap them between the two which are throwing the codes since they use different sensors.

 

I will never get why people start cutting, deleting or disconnection stuff. Scary to buy a car like that because you never know what else has been done to the car that you cant see. Good for you though that your are willing to figure all this out. Hope everything works out and you get that Z running correctly

 

im on a mission man, i really fell in love with this platform... but ... it has been a bit of a headache man.

 

okay so i totally forgot to mention that i actually have a regular DE in my car not a revup and i have another one that i recently picked up before i got this one and today i took off the sensors off that one and put it on mine but after swapping it, i swear the engine didnt feel like it was so accelerated but it was still idling at 1k, whatever i proceed to trying to do the ecu reset to see if that would help the TCS/SLIP turn off but the problem is that the check engine isnt even on and wont turn on through the process so i have to pop into a local tuner to see if they can reset my ECU. Another discover i found today was that if i put the car in 1st and take my foot off the gas the car just holds the RPMs at like 1,250 range like basically it wont go lower than 1k no matter what, i **** you not i drove it up and down the street without even touching the gas it was just driving itself like it was an automatic. i have no idea what thats all about, this may sound stupid but are there tunes that people do for that ? im hoping resetting my ECU will help with all this