Nissan fixed us up real good to prevent high speed driving...or so I discovered tonight. At 3AM, I was driving home and hadn't gone WOT on my car in a couple months. So....with the Torque Pro program and the OBD-II data logger, I was recording throttle position sensor.

Throttle position holds at 90% at WOT...until around 85mph. By the time you reach 85 and before hitting 90mph, the throttle goes from 90% down to 44% and stays at 44%. This is with the pedal to the floor. I did three runs from 50-90 at WOT and every time, at 85mph it was 90% and the ECU gradually decreased the throttle to 44% by 88 or 89mph.

Interesting, Nissan.

Late,
Trav

 

Yeah it keeps the throttle mostly closed from 0-40 as well. You can disable ETC with Uprev but it also disables cruise control.

 

That is exactly what I feel in the car. My '13 2.5 Altima pulled as hard as my Maxima over 80mph.

 

And I also watched the AFR. Anytime you go WOT, it goes to a big fat rich 10:1 AFR. I had just never looked at it until last night. Unreal...

Late,
Trav

 

Nissan is trying big time to reduce warranty claims. Do you notice how hard it is to go full throttle? That "button" is ridiculously hard to depress making most people assume they are full throttle when they are not. It is so hard you can not modulate the throttle the last 15% of the travel.

Regarding the throttle mapping. Nissan again is trying to reduce torque on the POS CVT. There is torque management from a stop and at high speeds. This is because there is the most potential for resistance from a rest and at high wind resistance (high speed). This is where Nissan covers their @$$ and reduces throttle. This car does not perform like a 290hp car should!

What bothers me is this; Nissan advertises 290hp but fails to disclose that 290hp is only available at specific times. It's like here you go, here is your 290hp car but only if your driving over 40 and under 85 otherwise it's more like 127hp.

Another example of this @$$ covering is the GTR. Take a GTR to a road course and lap it and there goes your warranty, straight from the horses mouth! In contrast Chevrolet won't blink an eye if your Vette was on a road course or not.

I have owned a few Nissans. Aside from what is in my sig you can add two more '13 Altimas, a Pathfinder and when I was younger I slept, ate, breathed Datsun 510s. This current Maxima has put such a bad taste in my mouth I am done with Nissan, I don't like the direction they are going.

 

It's even worse than that with the GTR. No performance mods whatsoever. They can also monitor the number of LC1's and LC2's the car has been put through. I think I remember reading that too many in a short timespan causes Nissan to flip **** if you try and put in a claim. There are all types of threads talking about this on the GTR forum.

 

This exactly! I can't wait to get a tune and disable it!!

 

Anyway around disabling cruise?

 

So they are using black box data to void warranty!?

What the fffffffak

Does BMW do this?

 

i dont think you can disable the throttle control without disabling cruise control. i believe it is, as mentioned above, Nissan's attempt to save themselves from a **** ton of warranty claims. its ridiculous that the GTR has a factory feature that if you use (launch control) voids your warranty. im not hating on the CVT as a technology, because snowmobiles have reliably been able to put out a ton of power from those kinds of transmissions and F1 racing banned them in 94 assuming whichever company mastered it first would dominate. I think because we chose Nissan, which is Infiniti's economy brand, we are stuck with economy parts. I love my car, but I think that is where we're at with it. It's a fantastic DD, frankly perfect, but as a performance car has left more than one person wanting more.

 

Agree!!

 

Does it do this in all modes to the same extend like in Sport or Manual mode?

 

yes electronic throttle control has nothing to do with what mode you have the transmission in, its always on unless disabled with tuning software.

 

Did the tune make a considerable difference in the way your car accelerates due to the ETC being changed?

 

the tune itself changed the way the car accelerated through afr adjustment and ignition timing alone so thats hard to say. cars at the shop having something done to it at the moment, when i retune im going to experiment with turning that on and off and comparing

 

That makes so much sense. I thought for the longest time it was a CVT efficiency problem past 85. More details on uprev?

 

Great, let us know please.
All I want is more more acceleration <85MPH.
I'm older now so for me this 85mph+ stuff is all "blast in the past" of days gone by.
Would be very content with something like +.2 to .3 tenths for 0- 60 times.

 

Sounds good, thanks for looking into it.

 

There is definitely a 'softening' of accelleration after 85 MPH, but that did not keep a stolen production 7th gen from leading Atlanta police on a 130 MPH plus chase through two counties earlier this week.

 

Is there a difference between the American Maxima and the Canadian Maxima!! I don.t feel that problem on my 2011 SV it pulls the same no matter what speed I am at and the WOT button does not seem to have any more resistance than the pedal!!

 

^ yea i was wondering if this has something to do w government regulations/to improve mpgs? That would explain a Canada/US difference. does the G37 have this? Its safe to say the altima does...... we cant exactly compare mpg's w Canada...

 

The 0-40mph acceleration isn't that bad on these cars. I logged the throttle position at WOT from 0-40 and mine showed 90% throttle by 20-25mph. I have Continental DWS tires, which have phenomenal traction and off-the-line acceleration caused minor tire slip. True WOT right off the line, I'm sure, would cause some major tire slip issues. Wheelspin from a stop is a surefire way to loose acceleration.

Late,
Trav

 

So at no point do we ever see 100% throttle?

 

The GTRs ECU has been reworked to allow Launch control and they dont void your warranty anymore if you go to the track. They void it if you over ride the ECU and then track it. Just FYI.

 

This is what the LC2 software update was for. Still can't modify the car though. Even altering the exhaust will void the whole thing, Magnus act be damned.

 

Most GTR guys who mod usually have 1 year limited warranties from whichever tuner they're using.

 

I figured out the throttle control retard out when I was racing my buddies Trailblazer SS and had him by a car + till 90mph when he barreled past me. Hooked up my Torque PRO and saw it for myself. These cars are very very de-tuned.

I didn't know that tuning the throttle retard off would also turn the cruise control off. Damn I use cruise all the time.
Still need to find a Uprev tuner close to Ohio that doesn't want $1000+ to do it....

 

Yeah its an electronic throttle control which is the same system the car uses for cruise control. From 0-40 I agree with Corolla it's most likely to help control torque steer. Regarding it closing from 90+ I have my theories, one of them specifically being we'd damage the drivetrain possibly?

 

It would be interesting to see if turning off VDC would prevent engine throttling at lower speeds 0-40mph as the manual states that VDC reduces engine output to reduce wheel spin.

http://postimg.org/image/z1ybe27jn/

Also, i believe i read somewhere that CVT's become less efficient at higher rpm's and generate more heat so nissan probably throttled it at higher speeds to prevent the transmission from overheating.

 

The traction control doesn't change the throttle cut.

 

http://www.nissanusa.com/buildyourni...m-(TCS)/Safety

yes it does

 

No more Nissans for me. I purchased the car so that I can drive as I see fit, in a safe way, according to local laws, not how an engineer sitting behind a desk see's fit.

 

The title of this thread is not exactly accurate. The Maxima can easily cruise at speeds over 130 MPH.

The complaint in this thread is that Nissan has set the car up so that acceleration drops off at speeds nearing 90 MPH. The only situation in which maximum acceleration over 90 MPH would be important is in racing, and Nissan does not consider this near-luxury family sedan to be a race car.

I am certain Nissan would void the warranty if they found the car was being used for high speed racing. I can't blame Nissan for installing whatever restrictions they feel are necessary to prevent that.

Nissan also limits the Maxima to somewhere between 130 MPH and 140 MPH top cruising speed because the car is designed as a family sedan with a sporting edge, not an ultra-high speed vehicle that would give cage protection to the driver and passengers in a high speed accident.

 

^^ Certainly has a point there.
You don't need your kids strapped in the baby seat doing 1G laterals plus the massive stress over the weak link cvts is where the torque management kicks in but again thats a feature on most vehicles now days

 

I agree totally. I typically stick to the speed limits pretty strictly. Just refueled this morning with 498 miles on the tank. 30.5mpg is one awesome thing about this car, if you're easy on it.

I just don't understand why they would even bother with allowing you to run it up to 130mph at half-throttle. Why not just put the speed limiter at 90mph, when they've obviously decided you don't need to push the car any faster than that? Know what I'm saying? I just don't see the point in even allowing the car to go that fast. I don't really give a hoot about going that fast anyhow and most people that purchase Maximas don't either.

Pretty sure it's in the warranty booklet that racing of any sort will void warranty. I think most manufacturers take that stance.

 

The CVT runs very cool. This transmission running hot is a myth. I've recorded CVT temps with some very abusive driving. High rpm generates more heat...just driving aggressively generates more heat. Nissan designed this transmission with the ability to shed heat very quickly at high speeds. It isn't a hot running transmission. Otherwise, I wouldn't have 95,000 miles on mine with the way I have driven it.

I'll link the thread I posted a couple years ago on it with the temps I recorded. Highway cruising at 70mph usually yields a tranny fluid temp of around 160-170ºF.

Late,
Trav

 

I wouldn't say the CVT is a cool running transmission. CVT's inherently produce more friction because of the metal on metal belt to pulley interface which is why they need special CVT fluid to reduce that friction. Nissan also touts their new CVT as having 40% less friction and how did they do that? by expanding the low to high gear ratio range so that the CVT can spin at lower speeds and generate less friction/heat. Cruising at 70mph is fine, but that's like hitting top gear on an automatic, if you want to go any faster, your engine has to spin faster and your transmission will spin faster. Since normal automatics are already "geared in" at that point, they don't generate much friction but CVT's will continuously generate heat because of the belt to pulley interface. Your car has 95,000 miles on it because you take care of your car and don't drive it to the limit. Nissan also has a fail safe built into the transmission to turn on limp mode if it gets too hot. When Car and driver tested the maxima, they had to do a 3 mile cool down run between each acceleration run because of the heat generated.

http://media.caranddriver.com/files/...axima-sv-1.pdf

CVT's are not cool running at high speeds and i believe the VQ engine is also not a cool running engine so heat is definitely going to be an issue when driving at higher speeds in hot environments.

 

..........

 

I'm actually really curious as to what the top speed of our cars is. I've been to 125 mph on a private road.

I know there s a police chase of reportedly 130 mph but I'm skeptical of that report.

Anyone else have top speeds?

 

I don't know what that link is as it's not pulling anything up related to this thread.

My point and I am certain is:
The TCS does not effect if the throttle is pulled back to 40% at 85mph or not. Ive tested it on and off and both times throttle is cut.