Sadly my G was also afflicted with the ECU upgrade problem.
But hats off to Legacy Infiniti in Lynbrook they have what are becoming a dying breed.
My complaints of hesitation seemed vague at best to the service rep.
After the sales rep explained that the ECU upgrade couldn’t be reversed I replied with well that’s unacceptable and I will want to see the service manager he said well let the service tech look at it and see if we “Find something” . He called me in later from the waiting room and said the tech has seen the problem and is applying a new bulletin that he has used before in this same situation. We’ll see how it works. Okay? Reluctantly I agreed. Well guess what? My G was back to its old self. I drove around all day with a big grin on my face reacquainting myself with my G. The symptom explanation for the bulletin was not in my opinion applicable to my problem or I would have noticed it before but the results speak for them self. And guess what the twitchy gas pedal is even better. Life is good. Bulletin number is ITB07-045a. Hope this helps.

ITB07-45a is the REVISED cold engine start TSB...just came out last week 4/27/09! Sorta ironic that there's a new ECU program that turns the car back to its old self. hahaha

One question - did you have a fluctuating idle issue after doing the sensitive throttle ECU update? If so, did this new updated (ITB07-45a REVISED cold engine start TSB) fix it?

Did anyone here on the forums that had it done actually like it afterwards??? i was thinking about having it done because because of that neck snap it gives me when i barely press the throttle.... it doesnt make it slower off the line at WOT does it????

I had it done and really don't care either way. However, like everyone says, it's definitely easier to accelerate smoothly off the line. It doesn't make it it slower off the line or reduce hp. Power delivery is more linear now. If you want to get off the line more quickly, just depress the throttle more.


What I don't like is the fluctuating idle issue that the sensitive throttle TSB caused. My local dealership confirmed that a handful of the ppl who got the sensitive throttle applied also reporting a fluctuating idle issue afterwards.

You can't take an ECU from one G35 and put it in a different G35. Well, you can, but the car won't start.

It is done this way by design. Dealers and most shops that flash ECus can fix this for you.

My '08G35x does not have the update and it's neck snapping responsive when you tap the throttle -- i LOVE THAT... and really miss this on my '09G37xS .. there is that numbness in the pedal when you tap the throttle from a stop with the 37 (i presume it had the TSB applied)

oh well...

try clearing the self-learn. this will basically reset how your car adapts to your driving.

remove the two battery cables and touch them together. this will drain down any remaining voltage in the system. all adaptives, presets, and memory functions will be erased.

worth a shot...

I just printed out both TSBs. i am going to take them in and tell them to do the first one and if i get rough idle then apply the second lol.

Could Infiniti just apply the latest version of the ECU and fix everything????

In answer to the question “Did it have a fluctuating idle after first bulletin” the answer is no definitely not. The idle was as steady as before. The only complaint was that damn hesitation. It was making me nuts. And worst yet it only did it in first gear and truth be told there wasn’t that much difference in twitchy throttle thing. Once out of first gear it was fine no hesitation in the upper gears. Like I said this appeared to me at first to be a questionable solution since I was aware of this bulletin already. But like I said before in my case the results were obvious from the first exit out of the dealer. And guess what the throttle thing is now quite acceptable. Hope this helps guys.

The fluctuating idle issue that I'm describing only happens when the car has been driven for a while and the engine is hot. And it does not happen ALL THE TIME, just occasionally. So, you probably won't notice a problem, if any, until you've had the car back for a couple days.

Besides, IMO you should drive with the less-sensitive throttle for a bit before making a decision.

Anyway, here are a couple examples of the fluctuating idle issue:

1) Idling a red light, you sometimes see (& feel the engine "shake") the RPMS drop to 400-500 RPMS and then go back to normal again.

2) Sometime when you start the car when the engine is still hot (e.g. after spending a few minutes in convenience store and coming back out) , the engine will crank normally, but the RPMs will immediately drop and feel like the engine is about to die, and then idle normally again.

To put it into definitive terms the car has never exhibited any of those symptoms either hot or cold that’s why I was reluctant to allow that last bulletin update. As a matter of fact other then the twitchy gas pedal and later that damn hesitation after the first ECU reprogramming. The engine was always real smooth at any temperature at any time weather stop and go or long trips. You’re right about it might be too soon to tell but it hasn’t run like this since before the first reprogramming. So we’ll see if it stays this way. In the mean while I got my old G back it’s quick off the line, consistent in any gear, smooth and composed. I’ve renewed my love affair.

Ernie; Where did you get the TSB ITB07-045a from?

Different strokes for different folks... I had the TSB work done and the acceleration did NOT suffer, the power comes on like a turbine, only now it is smooth and reliable.

Prior to the reflash (ie stock from the factory in April 2007) the throttle was a bit too sensitive; almost to the point of being a problem in slow moving traffic.

At the end of the day, the Service Manager should have been courteous and asked your consent. Imagine if you had paid US$400 for an aftermarket performance reflash (Techno Square) and had that erased

Here is a cut of the bulletin.
Ernie

Guys: There are now 3 TSBs for the 07 G35. The latest one issued April 27, 2009 according to Ernie3647 ITB07- 045a is not to be confused with ITB07-028 and 045 issued last year....all dealing with the "touchy Throttle issues. My ECM was replaced after the dealer applied the unauthorized ITB08-017 TSB, note that is an 2008. That made my G runa like an 08 which drive differently - slightly hesitant, etc. My g is CLOSE to what it was but not exactly. I do sense the rough cold idle. I may ask to apply the new 045a, next visit...