Her 350Z Failed inspection.
 

As you can see from the photo below, the girlfriends 350Z failed its inspection. She had the car worked on a month or two ago, and I am thinking/hoping the O2 sensor did not get reconnected or just needs replacing.

She said she took it to the part store and had them hook up a code reader. It did not show any codes.

My first big question is where is the O2 sensor located?

All help greatly appreciated!

Jeff

https://cimg0.ibsrv.net/gimg/my350z....15f9ac86fe.png

Your girfriend's car failed because four of the System Readiness Tests (SRT) were incomplete, or not ready. You can find a complete description of these tests in the Service Manual, but here's a basic description:

"System Readiness Test (SRT) code is specified in Mode 1 of SAE J1979. As part of an enhanced emissions test for Inspection & Maintenance (I/M), certain states require the status of SRT be used to indicate whether the ECM has completed self-diagnosis of major emission systems and components. Completion must be verified in order for the emissions inspection to proceed.

If a vehicle is rejected for a State emissions inspection due to one or more SRT items indicating “INCMP”, use the information in this Service Manual to set the SRT to CMPLT”.
In most cases the ECM will automatically complete its self-diagnosis cycle during normal usage, and the SRT status will indicate “CMPLT” for each application system. Once set as “CMPLT”, the SRT status remains “CMPLT” until the self-diagnosis memory is erased.

Occasionally, certain portions of the self-diagnostic test may not be completed as a result of the customer's normal driving pattern; the SRT will indicate “INCMP” for these items.

NOTE:
The SRT will also indicate “INCMP” if the self-diagnosis memory is erased for any reason or if the ECM memory power supply is interrupted for several hours.

If, during the state emissions inspection, the SRT indicates “CMPLT” for all test items, the inspector will continue with the emissions test. However, if the SRT indicates “INCMP” for one or more of the SRT items the vehicle is returned to the customer untested."

Did you clear codes prior to the test?.Has the battery been disconnected for a while?Usually when you have that many unset monitors it's due to the reasons I just mentioned.My advice would be to take the car for a good long drive with all of the accessories off.Get on a freeway and maintain a speed of around 90 km/hr or 56mphDrive for a minimum of 25 miles.When you start the car up.Let it idle for 5 mins or so after sitting over night.In my experience the evaporate monitor is the hardest to get to run/takes the most time.Also make sure your tank is more than a 1/4 full but no more than 3/4 full.
This is how we get our cars to get through their monitors when we have a car come in for a failed etest with unset monitors.Hope this helps

O2 are under your feet on the exhaust or cats. Should look like spark plugs with a wire to the trans. But that's a sensor. You have 2.

But I agree it's probably just a battery or electronic issue from sitting so long.

NissanZ,

As far as i know, the codes were not cleared before the test. How is this done. The car was worked on in Oct./Nov. She had to have the valve covers replaced along with some front suspension components and serpentine belt.

I am pretty sure they did not get everything re-connected afterwards. Her oil pressure gauge has remained nailed to the top end ever since. She has also been complaining of reduced gas mileage. Not sure how objective this is, though.

Oct/Nov seems to be plenty of time for everything to re-set, but I guess stranger things have happened.

Is there something I can do specifically to re-seteverything, or id driving the car and letting it do it's thing the only way?

Karl,
Thanks for your reply. It's a reasonable explanation of a process that is way over my head. Are there any steps to get everything to re-set, or has NissanZ covered that?

Assuming everything is reset, and there is something actually wrong, my first thought is replacing the O2 sensor. I am also concerned about the catalyst failure note and her poor gas mileage. I am assuming we are talking about hte catalytic converter here. Could problems with the O2 sensor cause the motor to run rich and foul the converter?

Will this clear up once the O2 sensor is good?

Hoping it is all in the electronics, but trying to plan ahead a bit...

Thanks,
Jeff

Not ready means you need to drive the car to ready it up. Could take 20 miles could take 80 miles. Based on my inspections I would say it's closer to the 20 miles for the 350z

Go for a good long drive and then go to a autoparts place and have them check to see if any new monitors have set.If they haven't it's likely there is another issue causing them to not run.Has the Z been tuned/flashed?.It's really tough to go any further without seeing the car myself.Don't just throw parts at your car though please!.It'll just cost more in the long run.
Goodluck!!

i think you can have 2 not readys and pass... but makes me wonder if the car has been tuned

TAZ - As others have said, you need to drive the car to set the monitors. The Service Manual describes a driving profile to properly set all the monitors, but a good long drive should suffice.

It's conceivable that whoever worked on your girls car a month ago probably disconnected the battery, and as a result reset your ECM; which in turn caused the car to become 'unready' for inspection, and since/if your girl doesn't put enough miles/time driving the car and putting it through the motions during that month, it's going to stay 'unready' until she does.. btw That drive cycle in the manual is ridiculous(right or not) and virtually impossible to follow while driving safely.


Like stated above:


- Drive on the highway for like 30 minutes.
- When you come to a stop, put the car in N, then P, then D.
- Find a back road that you can do a sustained 30 - 55mph for 20 minutes.
- Accelerate from 0 - 55mph normally and sustain that speed for 10 minutes.
- Stop the car, then move the shifter to N, then P, then D.


You should be ready now. Also, I'd pick up an OBDII scanner so that you can monitor the readiness yourself. Good luck.

The car has been driven from Austin to Houston (125 miles) and back at least twice since the trip to the repair shop. Apologies for not remembering this earlier. It's also had a couple of months of commuting to work. Surely that is enough to reset everything.

You could have a weak battery.. The ECM will suspend the drive cycle if it's not happy with any aspect of the charging system.

The OBD connector is powered through fuse 34 directly from the battery. The power sockets are powered through fuse 7 and only with the ignition key in ACC or ON. I don't think your problem is a blown fuse. If you have any questions, please download a copy of the service manual and check the schematics yourself.

>EDIT<. My previous response in this spot may have indicated the problem was solved. Alas it is not.

I returned to the inspection place this afternoon, and the problem is still not fixed. Same four items are reading as incomplete. The last time the battery was disconnected was when the car was worked on in November. I am stunned three months of driving is not sufficient to CMPLT all the SRT stuff. I am also baffled at how the Inspection station can read the data port, but code readers at three different part stores and mechanics cannot communicate at all.

The service manual (at least the part quoted by Karl says:
"If a vehicle is rejected for a State emissions inspection due to one or more SRT items indicating “INCMP”, use the information in this Service Manual to set the SRT to CMPLT”."

Does this refer to something specific that can be done in the shop to set an INCMP to CMPLT, or is the procedure they refer to driving around?
Is there any way to know the status has changed to CMPLT other then a trip to the inspection station to get the codes read again?

so it passed inspection when you took it?!?

No, it didn't. See edited post above. I was on the side of the road using my phone to post to the board, and did not proof read my entry. My bad.

Jeff

:icon22:

Karl,

Thanks for the correction. The parts store folks told me it was the power socket fuse. Serves me right for not checking the source. The Service Manual certainly has a LOT of info. The PG section shows fuse 34, but it is not clear where on the car that particular panel is located. edit: Crap, it's not the one next to the battery, is it?

Also thanks for the earlier explanation. It has taken me a little while to wrap my head around this and understand what is going on. Still very frustrating...

Jeff