This link is for the original topic:

https://my350z.com/forum/showthread....highlight=1283

I subsequently trashed the threads on my lower plenum durung all the re-installs as I tried to trouble shoot the code 1283 I got shortly after installing the MD IsoThermal upgrade.

Well today I installed a new lower plenum, removed the Iso gasket and went back to the OEM, and removed the plenum spacer. In other words all is back to stock except I kept the AFE Intake on the car.

Well after driving around trying to have the 1283 code come back, no such event occurred. It could have been an air leak I suppose and doing the entire install and going back to stock may have fixed it.

I guess time will tell if the ses light comes back on. It usually only takes a few miles and about 15 minutes. I tested things out for more than that and no light.

If it doesn't come back I will carefully reinstall the spacer but not the IsoThermal gasket. I kept the coolant bypass to the TB in place. I wasn't really getting much results from the gasket anyway. The pre temps were 127 to 130 degrees and the post was exactly the same. Don't know why but it doesn't seem worth all the work to put it back.

Hopefully the SES light will stay off and I can put my spacer back which did make a significant contribution.

 

Oh well. I spoke too soon. Although I couldn't get the light and code to come on last night. It came on this morning within 15 minutes of leaving the house.

Now that everything is stock under the hood, it's off to the dealer so they can figure this out. Hopefully it's just the AF sensor as some have indicated as a common problem.

 

I recently spoke with the service tech about a rough idle on my G35 and they fixed it with a updated factory spec ECU reflash.

I asked them specifically what was problem and they could only tell me it was a TSB related issue that required a new ECU software operating system.

Aparently there is a bug in the 2004.5 software code that can cause an anomoly on "Bank 1". This can cause damage to the O2 sensors by putting current to them to the point of overheating and damage.

They flashed in a totaly new operating system to my ECU and my car runs great now.
Could you have the same problem?

 

Good info to have as I go to the great wilderness known as the Nissan dealer. I will mention the TSB and see if the 350Z has that issue.

Thanks Tony

 

ZinMiami: Did you ever resolve this issue? I seem to be getting the same thing, and I have many of the same mods as you do. Any help is appreciated.

 

I have done some further DIY investigation but have not had time to leave the car at the dealer. Hopefully I will be able to get to this in the coming week. I will post my results in any case.

 

Please keep us updated. I recently have been getting the same code. 1283 & 1274.

 

with this factory update on the ecu; will it erase my turbonetics program?

 

Yes. It certaintly will. You might want to contact Turbonetics and see if they have the latest revision from Nissan with their own custom code added in.

 

I recently had such a problem...
FYI: Took my car to dealer to put my car back to stock suspension (OUCH)
after that being done, right after i made 2 turns from the dealer and stopped
at the light, ALL FREAKING dash lights came on.. and my car lost power. Then, I had to shut it down and restart it to regain power (But CEL stayed on), took it back to the dealer, got them check at the codes. They did a print out of the code, but they couldn't find any problem with the codes given... and the light never came on again...

Yet, they suspected that it might be a throttle body sensor problem..

Do i need such a reflash? (my car is a 04 G)

Mans

 

Reflash? Probably not. It doesn't sound like the same type of problem.

I suppose a dealership reflash update couldn't hurt though.

 

Any updates? was it the O2 sensor?

 

Well here is whats gone on to date. On 12/23 I begin hearing a nasty sound from below. It turned out that I had exhaust leaks caused by cracks in both of the downstream pipes of my hi-flow cats. At that point I was getting not only 1283 but 1273 codes.

I had the pipes repaired and reset the codes. I didn't use my car over the holiday weekend but as of today, 12/27 a couple hours use has not had the codes return.

I am hoping that the initial 1283 was caused by a subtle leak from one of the pipes. Both codes became evedent when the leaks finally became serious to the point where I could audibly detect them.

Leaks in this spot would cause a lean condition I would think. Hopefully this will be the case and I can move on.

We'll see with time.

 

ZinMiami: Thanks for the update.

This might be the source of my problem too, since I too have the Helix cats and have an audible exhaust leak

Man, I've had the worst luck with exhaust components on this car, first a cracked Gruppe-S Y-pipe, and now potentially messed up Helix cats too. This really makes me want to go back to stock and say screw exhaust mods

 

1274 and 1283 with the Turbonetics kit only:

Check your downpipe. You should have about a 2" O2 spacer welded onto the pipe where your O2s go. If not call Turbonetics and they will send you the new downpipe.Its easy to distinguish since if you look at the O2 sensor (rear ones) they should be screwed into a thin piece of pipe that is like 1.5-2" out of the downpipe. If you have those you will need to do the ECU update and get the ECU reflashed by Turbonetics again.

 

.....I dont have the spacer...and I have both the 1274 and 1283 code....and I have already bought a pair of O2 sensors...

How do I do the updates? ECU and downpipe update?

Oh BTW, now I have a over boost problem that werent there before. When I first Dynoed it it was at 8.7 psi max and running rich at 10.5 AF WOT.

I havent dyno again yet, but when I do my pull on the freeway in 4th gear...10.5-11 psi~!!!...at 11.00 AF. I have no idea whats going on. No, I havent done anything to the car since the install....I dont get on boost now...I need to get it fixed cuz Im getting sick n tired of being picked on by Ricers...

 

I'm so glad its not only my car. I had the exact codes on my 2004.5 Z roadster after my APS TT. After installing the APS exhaust and test pipes, the codes went away. I think the test pipes made the difference. Does any one have the official TSB name for the fix? I think the test pipes is only a temporary fix and would really like to switch back to high flow cats.

 

In my case I caused the leaks. I thought it would be a great idea to have a couple brackets made and welded to the Helix cats to provide support via the OEM cat support bracket. Well I guess not because that is the location where the pipes cracked. Right at the welds on the custom brackets!

Not such a great idea afterall!

 

Well this is hopefully my last entry on this issue. I drove my normal course today which usually triggered the codes within 15 minutes of reset and no codes yet!

The leaks must have been going for some time. It just took them some time to become detectable.

So unless the SES comes on later today this issue is closed for me.

Thanks to all that helped out along the way.