Ok, there are some things that need correction.
1. Fuel cutoff is not necessarily associated with braking. Whenever a car is under speed and the throttle is lifted, fuel cutoff serves to act as an economy measure. The driveline will keep the engine under rotation without need for fuel, so even the idle circuit fuel volume is cut. When the engine RPM drops to a pre-determined point, the idle circuit is restored to keep the engine from dying.
Under instances where the throttle is being depressed, fuel flow will not be interrupted, even with the brakes applied. This is commonly referred to as power braking. Drag racers will do this all the time to remove all driveline slack before launch, to get engine rpm up off of idle and preload the automatic tranny.
It would not be beneficial to always have power cut when the brakes are applied even though under most circumstances that is what makes sense. Left foot braking is common with racing, but not with everyday driving. So throttle lift does occur with normal driving since the driver uses that foot to brake.

2. Just because engine rpm rises, doesn't mean that power is being applied. It simply means that the engines relationship with the chosen gear and forward motion must be maintained. Both 1st and 2nd gears are very steep in the G37, so if a forced downshift occurs via driver input selection, a corresponding leap in RPM is going to happen. The same is true for the 4th to 3rd shift since the gearing there takes a big leap as well.
If the vehicle is near dead stop, the selector is in DS, or forced into 1st, it will bump the throttle to rpm match. This will cause the driver to wince if they are not expecting it and their braking distance is short.
While it sounds cool to have throttle matching with an automatic, it really isn't necessary. The drivetrain tends to have enough built-in slack so that the downshift doesn't jar.
Smooth shift transition is really the only reason to have throttle matching, and with a manual the driver has to do it, (or not). Automatics don't really need it, and it is a gimmick. Keep in mind that any throttle bump on a automatic will correspond with LESS engine braking for a brief instance. With a standard transmission the driver is using it to pass between gears and there is neutral driveline effect.

If you desire smooth and more continous driveline braking, leave it in "D". If you expect to pull the car's speed gradually down over a distance then shift it down manually. But you must be aware that those rev matching events will occur with every downshift.

Actually the G's 7AT already does very aggressive engine braking when left in "D" more so than just about any other automatic. This is seen easily in every 'slow to stop' and it shifts from 4th to 3rd. The RPM jumps, but it doesn't equate to power actually being applied.

While there might be a flaw in the engine fuel management system to cause an accident, it does not equate to what people commonly see in driving this car. Most of the uneasiness people have is more likely due to the unfamilarity of the vehicle and the way it is designed to operate. Even more likely it is because they fail to observe a more cautious driving habit and that coincides with the design to bring about an event of "leather suction".

 

Gimmick or no, I LOVE the rev-matching capability of Infiniti's 7AT! It works really well even in everyday driving...

 

I experienced an unwanted increase in speed from 75 to 80 mph for several seconds after quickly accelerating around some traffic, 65 to 75 mph (no hills involved, in D mode). There no doubt was a downshift to 4th gear, then an up shift to 5th, after finishing the pass, at some point, after letting up on the accelerator pedal. The rpm stayed higher than needed and caused the extra increase in speed in a glide situation. This action seems to have disappeared after the software update. Maybe that action fits the profile for a racing situation that the G37 is supposed to emulate.

There was also occasionally excessively high idle rpm (say 1700) when already for some time in 1st gear after letting off of the accelerator and braking, for instance, when coming to a stop in my garage. Very unnerving, but went away after the ECU software update from 70c to 86a. Since the problem was not consistent, I could not predict how to control the vehicle. I think this is what some are still experiencing, and I believe the software update should be a recall issue.

However, no doubt there are times when bigfoot lazily overlaps the accelerator pedal when braking, causing surprise surges as well. But that probably accounts for only 10% of the unwanted surge issues, if that.

I still see the O2 sensor voltage, normally 2V, goes to 5V for a few seconds after letting up on the accelerator, which indicates an excess of fuel was unburned in the exhaust. Hopefully normal for this engine, but is it a waste of fuel? Or like seemingly excessive military supplies, you do not want to fall short in a crisis.

At this point, with all the warranty repairs, and software update, the car seems better than new to me. But not quite sure if the overall reliability is going to be there after the warranty expires. The car has performed flawlessly on hot, long mileage trips with steep mountain roads, so I should not be too critical. But my Taurus hung in there as well. Time and mileage will tell.

 

Yesterday I got to a red light, put the car in neutral and was waiting for the light to turn green. I look at my rpms and they are steady at 3000 rpm! I pushed the gas pedal down a bit and then took my foot off of it and it stopped. I figured maybe the OEM rubber mat unclipped and was putting pressure on it. Checked the mat, it was fine, still clipped in. Next red light comes along, get into neutral and I see the revs slowly spool until about 3000rpm. I put pressure on the gas pedal and release, back to normal. I then get to a stop sign and notice the exact same thing happen again... This is something to be concerned about. I then turned the car off for a few seconds and started her up again. Nothing has happened since.

My car is an 09 G37S Coupe 6MT

 

i have a 2010 journey that jerks forward when i drive in DS. it always happens when the car is trying to manage its downshifting as i slow down. Any other 2010's have same experience? i guess i will mention it to the dealer

 

As others have said, I believe that is a function of engine braking and rev matching. First time or two it caught me off guard when braking fairly hard...but there is a purpose related to the sporty nature of the car. Only seems to happen in DS mode....helps slow the car down and would be a really cool thing if you were driving aggressively and needed to go back and forth between braking and acceleration such as when driving aggressively in the mountains. No so good when driving in traffic, but would be awesome on the race track or in the hills. Just drive it in D if it bothers you.

 

I have experienced something similar to this situation twice. I was stopped at a red light and i eased off of the brake a little to ease up. To my surprise the car surged forward. Shocked I tried it again and it did the same thing. i also noticed that i had to apply more brake pressure than normal to keep the car stopped. i turned the car off then back on again and the car was back to normal. Has happened one more time since then. Im scheduled for my next oil change soon, i'll have them check that out then. Though i doubt they will be able to duplicate.

 

The G37x we own is my wife's car, but I found that I accidentally found myself pressing on the accelerator while trying to brake. Compared to my car (5 speed Honda Element), I found the brake and accelerator pedals to be close together, causing the problem. It's happened several times, sometimes quite alarmingly so. I have wide feet, but not THAT wide!

Seriously though, the proximity of brake-to-accelerator pedal is too close for my tastes. I have to remember this quirk when I get in her car.

 

I captured mine on video. Started a new thread, check it out.

https://www.myg37.com/forums/engine-...ml#post3019549

 

For the record, it happened to me on my 2010 G37XS Auto Sedan a few weeks after i received it (three months ago). Was stopping at a light and the RPM started to race upwards even after I was at a full stop. The brakes held it but it was scary! The guy stopped in front of me was looking at me like I way going to ram him. Took the car into Englewood, NJ dealer and they looked at me like I was crazy....they found nothing wrong. Hasn't happened again since.

 

I had the same issue with my 2008 G37 S. Without notice the car would start bucking while the RPMS jumped up and down. The only way I stopped it was to turn of the ac or power the car off.

I will be contact Infiniti of America consumer relations department and I feel all who are having this issue should do the same.

 

I will chime in as well per previous post.
https://www.myg37.com/forums/g37-sed...too-close.html
This is the first Nissan product I have owned (been a Honda guy, mostly MT). I wear a size 11 shoe and have to be very aware of foot placement on the brake pedal.

 

Does ANYONE have a final and definitative answer re: Throttle Surge issue?

 

I don't see anything wrong with the way the car downshifts.

Some of you need to understand that you can't have a sporty downshift and be smooth at the same time, especially if you're braking hard. You would need lightning fast shifts in order to smooth it out. Even the double-clutch manu-matics are clunky at times and those trannies are way faster than our torque converter tranny.

If you're driving casually, take it out of DS mode. The only other solution is if Inifiniti programmed it to never downshift and wait to do it when throttle is applied. This would be like the old-fashioned automatics and who the hell wants that?! You want the car to downshift *before* the corner so you can be in the powerband to modulate during the corner and power out of the corner.

If anything, Infiniti needs an even more aggressive shifting algorithm to alleviate the lag that a lot of people feel.

 

People pressing the gas with their foot while they're braking. It happened to me a couple of times when I first got the car. I wasn't used to the gas and brake being so close together. Now that I'm aware of it, it's never happened again.