Ecu tuning 2002/2003 g35sedan (very technical)
 

Could use some knowledge junkies on this one.



My current situation with ecu stands as follows:


I have the early model ECU harness the one that nissan used on the 2002/2003 Maxima. The connectors are completely different than the ones from 2003 + G35's.

There was a thread on frenzy which some have followed yet since I moved i stored the wiring and completely forgot about it till recently that I was cleaning out old junk and :eek: found the harness..

a bit old but anyone want to look here you go (pics somehow got erased)

http://www.mygfrenzy.com/forum/showthread.php?t=8708


I have a couple of questions regarding current ECU mods.

Till about 30 minutes ago I thought that the UTEC was a complete EMS. I really thought it took over the entire ecu and allowed you to use the stock functions of the car. With said I then researched the AEM EMS, and noticed that AEM is not working with the G/Z in the EMS side of business. So that leaves me with 2 more options. HALTECH or Upgraded ECU/ADAPTER

With those choices brought up my question then stands is the Haltech a FULL EMS? By full I mean it will completely replace the ECU from engine functions, lights, wipers, horn, CEL's, RPM, TACH...

My goal is to have a ECU that allows stock functions of the car but allows me to tune the car to my specifications.

I understand that Uprev has the Osiris upgrade, but again the ecu i have is not supported.

The next option on the table is to go to the dealership get a 2003 ECU (which has the correct plug) have Richard of AutoSport wiring make an adapter from my harness to the new ECU and then use an Osiris to program the engine.


What is the major difference between the ECU's other than the connectors?

I know that one of the ecu's (not sure which quite possibly the new ones) have the feature that it continues to learn a persons driving habbits and adjusts by monitoring the oxygen sensors.

Will I have to upgrade the wiring harness from the earlier models?

Will there be a problem with the chip inside the key?



What other FULL air, ignition and fuel tuning options do I have (other than Technosquare)

I would do the technosquare option but I prefer the simple fact that today I can go to the dyno tune the car to my wants and then take the car to the track and revert the car back to it's elder settings, or even putting the car in valet mode, etc...


Ideas anyone?

Any one else with potential ideas, or am I the only one interested in Pioneering this ?

Updates
 

Ok, for those whom have been following (I've noticed the views).

Here is the new idea:

I consulted the mechanics and service techs @ South Motors Infiniti here in Miami, FL. Yes, you can use a 2004 ECU on a 2003 G35; YOU MUST have the cables crossed over to allow that ECU work. Once that ECU is operational, then you have to relearn everything. Throttle, idle air, KEY CHIP, etc...

With that being said I have yet to contact UpRev, but I am sure once that ECU is in place they can then provide tuning abilities.

Richard Welch of Auto Sport Wiring is again reviewing the tasks to be involved and I must say he is a SUPER guy! If this can be pulled off it'll be nice for the 03 Sedans on here that want to put on cams and actually TUNE the engine, have the ability to change maps/tunes via cruise control, go FI, etc..


TTRANK, do you have any experience with the UTEC? Is it any "better" than the Osiris system?

Any tech heads DROP IN!!! :)


I have attached schematics of the wiring crossovers and OEM pin outs to each respective ECU.

The pin outs are directly from the tech manual from Nissan/Infiniti just made easier to read.

I've done alot of research on this before. I asked Cobb to do it and they planned and then quit. UpRev was going to try it if I sent in my ecu for them to flash. Experimental. I said forget it.

Guys on the maxima board have already custom made a maxima harness (ie.. early g35) to hook up to the UTEC. But you are right, it does not have full reflash capability like Cobb, Uprev Technosquare.....

If you are going FI, then you're going to have to probably hardwire in a Greddy, UTEC, Haltech etc.... and bite the bullet.

If NA, I would just send it in to Technosquare. That's what I did for my early G35 sedan.

Technically, Uprev's reflashes have more control than the UTEC. Even for FI they can handle alot of power capabilities. But alas, our versions aren't supported. Too bad as they could pick up alot of the maxima crowd along with the early G35 sedan crowd. Probably Altima guys too

Funny enough 5 hours after my proposal to Richard @ AutoSport someone from the Maxima family contacted him to attempt something similar.

The Maxima connector is the same but some of the pin outs are different.

Problem with the Greddy is you only have 2 Dimensions of tuning, air/Fuel. You dont have control of timing. the Ecu would overide it. You can't alter the max values of the Throttle our cars stock only go to like 80% throttle, rev limit, etc..

The Haltech is an ARM and a Leg. No doubt a full stand alone is the best for any performance gain, problem I see and perhaps __Jb can confirm or rectify... that going FULL stand alone you loose the chip ability, and few other essentials as cruise control.

attached is the maxima pinout

I'm is SoCal, so i just drove to Technosquare

How much was your tune at technosquare and what was the difference between the $300 and $500 dollar one

Haltech is not a full stand alone, it still uses the factory ecu for certain functions.

Not entirely true. I have a Greddy Emanage wired up since there were no options with COBB, UTEC (without wiring harness), Osiris, etc.

The Greddy allows you to have full control over TIMING and AIR/FUEL when at WOT. Additionally, if you have the Emanage Ultimate you can bump up the rev limit. Its been done several times, I think the maxima guys were the first to do this. Also, the EMU has a knock sensor, dual map quick flip switch.

As for the TB going to 80% there is no control of that yet (at least that I'm aware of) but I've also been told that some tuners looked and did not find this 80% Throttle suppression.

iirc Emanage (blue) only allows for Air/Fuel. Timing is not controlled.


I've been busy but plan to send out the harness this week so Richard can get started.

Following with interest but TBH if I really decide I want a tune I'll probably just ship my ECU off to TS and drive the wife's SUV for a few days.

I think emanage only has timing retard and not advance?

I believe so.

You sure Uprev won't support your ECU? In the manual it mentions that your ECU (gen1) is supported but just won't have map switching capability. There is another document about rewiring the CAN bus on the '03... but maybe it applies only to Z's?

Going to bump this up.


At some point when I start doing more in the way of engine mods, I'll be interested in tuning, but I'm in the same boat (03.0 w/ old computer)

I had asked if it could be adapted to the newer ECM in another thread, but got no responses.
Have you made any progress on getting an adapter made?

I guess if someone wanted it bad enough, and could get their hands on a junk wiring harness, they could de-pin the connector.
But that would be a lot of effort for something that might not even work properly :/