Hello, I am in need of some help. Been having lots of random codes and rough idle. Please don't tell me to take it to a professional, done that, and they weren't of any help. Plus I've rebuilt, swapped, and worked on many cars, so I'm not a noob when I comes to these sort of things. Anyways here's the story.
Bought an 05 350z anniversary edition a while back, drove it for about 2 years with no issues. So I decided to do a 6mt swap (the car used to be a 5at). FYI the car only has 32k miles. Completed the swap, and everything went somewhat smoothly. Here's what I swapped/did;
5at to 6mt transmission including the hydraulics, flywheel, clutch, (everything mechanical etc...)
2005 5at ecu to 2003 6mt ecu - brought it to a locksmith, he swapped the eprom chip in the ecu to allow the ecu to mate with my keys
5at to 6mt engine harness - o2 sensors were different, 5at harness had wideband upstream, 6mt came with the narrowband o2, so replaced those with narrowbands (new ntk sensors)
wired clutch pedal safety switch to ipdm

So the car started up, at this time I had the 5at ecu still in the car. The car drove great, but I felt a slight misfire. Also I got some u1000 codes, (obviously these were because it noticed the missing 5at pcm), and also had some o2 sensor codes, well these were due to the the narrowband o2 sensor voltages being different from the original wideband, so it confused the ecu...at least I'd think so. Brought it to the locksmith and had him install my 03 6mt ecu that should've worked with the narrowband sensors. I started it up and it ran, and still does, but I have 2 u1000 codes, not sure why, and a whole bunch of random o2 sensor codes (when I clear the codes, they come up for different sensors). The car still idles really rough, and I think even worse than before. almost at 500, a little bouncy, and a lot of slight popping/misfiring. Sometimes wants to stall. So I went ahead and replaced all the o2 sensors, and same issue. (I pulled those back out and returned them). I also swapped the engine harness with an extra one I had lying around and that didn't fix it.

Anyways this is getting long. I don't want to keep stabbing in the dark, and wasting money for no reason. But I have eliminated the engine harness, o2 sensors, and the only thing I could think of that could be causing this problem is the ecu. I was going to go ahead and purchase an ecu from a 2005 6mt 350z, and engine harness, and pop back in the old widebands that I originally had in the car, but I thought maybe I should see everyone else's input, maybe I'm missing something? I haven't really had luck with these forums, but I thought I'd give em another try. Any input would be greatly appreciated.
Thanks in advance, I hope I get something.

 

I believe you're going to need an ECU from a 2005 6MT. The fuel tables are different from 2003 to 2004 and after 2004.5 the ECU uses totally different coding altogether, as well as stricter emission control programming.

 

Hi Mustaffaa -

First things first, if you're in Seattle, you're not going to be able to tab your car the next time you go in for an emissions test. In WA, you cannot put an older ECU in the car than what is indicated on the VIN and still be street legal. You're going to need to yank out the 03.

Your car needs a 2005 MT-programmed ECU, so that's what you'll need install.

There are many evolutionary changes between the programming in the 03 and the 05, so it makes sense that your car is running poorly right now. I know that others have done AT-MT transmission swaps on their 350Zs successfully, but I've never heard of anyone going with an earlier-model ECU as part of the process.

 

Awesome guys! Thanks for the input. I thought that might've been the case, just wanted to make sure in case I were to make another mistake. So I am planning on having my original 05 ecu reinstalled, install the 05 harness, the wide-band sensors, and do some wiring. As for the check engine light I will most likely get, I plan on just having those codes removed via a flash. I also ordered a 6mt guage cluster, once that comes in, will have the ecu and odometer reprogrammed for my car at the same time. Will make an update post once everything is sorted out. Thanks again guys I really appreciate it. It changed my original perception of this forum, I guess its not so bad

 

I don't understand why people swap the ECU when they do a 6mt swap.

I did one on a 05AT and did not swap the ECU. Had my tuner delete the u1000 and other related codes. Passed emissions fine with two freakin turbos on it.
Way easier that way.

Put the old ECU and o2's back in it and call it a day....

And there is no reprogramming a 5AT ecu to 6mt, if anyone is thinking that, not that it was insinuated here. Just run the 5AT ecu that came in the car and you will be legal and happy. The 6mt gauge cluster won't work as far as I know, but if you've read it somewhere go for it. I dealt with the blank gear selector and tranny light but that is no big deal

 

Thanks for the input man, will be dropping the 5at ecu back in asap. And for the 6mt guage cluster, I actually have one currently that I got with the tranny (its custom, hate the look of it), and it works perfectly, even the shift light works as well! So for anyone looking to use the 6mt guage cluster, I say go for it, works perfectly for me

 

That's pretty cool! But what about with the 5AT ECU?

 

Yep, works with the 5at ecu. When I had the 5at ecu in the car, I also installed the 6mt guage cluster to see if it works, and it does. Doesn't effect any of the electronics or anything like what I read in some other forums.

 

Would have been nice to know this last year!!

 

I'll be doing it this summer/fall. Should be fun.

 

Nice, its not bad as long as you have a clean place to work. I decided to do mine outside since I had my G in the garage, and it started pouring rain for a day in the middle of the swap :I so there was a lot of rushing. Although I did manage to pull it undercover once it all cleared up, and it wasn't so bad

 

Yeah, I've done AT/MT swaps in the past. Mostly on pre-1980 muscle cars(Camaro's, Corvette's, Trans Am's, Chevelle's, Javelin's, Nova's, etc). At work, I usually replace 1 to 2 trannys a week; typically on diesel box trucks and LLV's. So this will be the first import sports car I do.. I like working outside, so it all depends on what the weather's like that week. If it's supposed to rain I'll just do it in the garage.