ECU Adjustment - Further Observations With Test Pipes

[Jacko3]

Anyone notice that our ECU's adjust for either WOT situations or gentle driving without your knoeledge? Our ECU's tend to retune itself each time you add an engine modification. Isn't that amazing? Its like our cars are self-healing engines--I thought this was stuff that was only applicable to the GTR. And I bet our transmissions does the same as well---anyone notice that a 6MT drives extremely smoothly under WOT than in gentle driving? I feel every owner of the G-35 C or Sedan or the 350Z is already enjoying some prtions of the GTR technology already. The GTR in my opinion, is just an advanced 350Z on steroids.

I say all this because since after adding test pipes to my current modifications, it seems the ECU leaned out the car a little as the 02 sensors were now in more contact with the escaping gases than before. Leaning out shoudl raise the temperature of the ngine, but it would appear that the Mobil EP 5W-30 Synthetic oil is doing a great job of almost eliminating any signs of heat after a driving session.

This reduced heat production, a swithc to Chevron premium gas which cleaned out my injectors very well, and leaning out of the engine, would explain the impressive gas mileage I have been getting so far with the car (27 MPG to 30 MPG) since after I installed test pipes---my mechanic tells me that the onboard computer MPG reading is not so different from the actual MPG if calculated manually--difference could be 1 - 2 MPG.

I also noticed that the ECU has even gone as far as retuning even the exhuast sound. Its now slightly less aggressive as when i first installed the test pipes. I find this amazing and really satisfying. What it means is that the G-35C is built with so much room for adjustments such that it is next to impossible to damage that engine unless through owner error or ommission. This is my first time driving a car that literally fixes itself so that it does not destroy or damage itself.

I am willing to bet that my car will pass emissions now without cats. The exhaust gas smell that used to be overwhelming when I first installed the test pipes, is virtually gone or extremely reduced.

All this engine management magic seems to have taken sometime to adjust and fix--it took almost one month for all this to occur. With my first set of mods---air intake, spacer , mrevv, and cat back exhaust, it took about 3 months for the ECU to adjust properly to those additions.

I am really impressed by all this. What does anyone think about our cars on this subject?

[Sentientbydesign]

Jacko,

I completely agree with your opinion regardin the transmission. It "hates" to be driven passively. I was in bumper to bumper traffic this morning because one of the lights on the way to work was flashing red for construction work and I drove the G lightly in 1st hoping to not have to take it out of gear and the car felt like it was going to fall apart.

I get on the freeway going 70, then 80 and it's a completely different animal. Since there is little to no electronics in the transmission, I'd say it was just the way the transmission was built, not that it actually adjust per say.

With regards to the sound of your exhaust, I think that's just wear in. I've read quite a few accounts of exhaust sounds mellowing out after being installed for a few weeks.

I also agree regarding the adjustment of the ecu to your driving style. I remember resetting the ecu and throttle release learning and getting a completely different response from the car. Taking it easy for too long seems to make the throttle open up slower on acceleration.

[Jacko3]

Nate:

All I can say is that the G-35 and 350Z, as imperfect as they maybe sometimes, are a Japanese product of marvel. I don't think Nissan cares to tell us and their dealership mechanics how and what other miracles these cars can provide and accomplish.

It seems the funny rattling sounds were deliberately built into the engine and transmission as margins of error. It appears the car's mechanical and electrical parts were designed to get better as the car is driven harder and longer.

Have you noticed how quiet the engine and transmission gets after some serious flogging, but the same engine and transmission rattles when it cools--very strange Japanese design ideology. That is sports car design in a street GT car. And this probably explains why the G-35 can take unbelievable driving abuse and punishment like no other car that size I have ever driven before.

I love this car with all my heart. Nissan built an almost indestructible machine and then handed it to neophytes like us to do what we please with it. I have no doubt that the G-35 Coupe and 350Z are Skylines in disguise. Nissan used both vehicles to get the skyline into the US at all cost. Now I understand why people will do anything to get a skyline into the US even if it means going bankrupt. I had no idea until now.

And then Nissan has gone as far as even lying some more with the understated power of the GTR to bring it in to the US as a GTR without the Skyline logo. The GTR will always be a Skyline GTR in my mind no matter how much Nissan wants to lie about it.

Well done Nissan! I love your auto company. You understand cars like no other.

[kmckis1029]

i read the auto transmission adjusts its shift points according to how you drive... i have noticed that since i brought the car the transmission holds 1st and 2nd gear longer to satisfy my more aggressive driving... plus the throttle response is much better, then add SBD's grounding kit to help the computer learn more accurately i only had my g35x for just about two months but i'm convinced my next car will be another infiniti