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Discussion Starter · #1 ·
Recently, I realized that I am having lagging in term of power. I have to push harder to get the power comes out faster (a little slower than before).

I came to two conclusions which might cause this since I did not have it earlier (or just my imagination).
1. Since new year, the traffic has been heavy and I am guessing the engine learn my driving behavior. Should I reset the ECU? (haven't had a chance to do this yet)
2. I realized this after my first maintenance. The dealer uses conventional oil. Is this a reason?

mileage: 5000 (Q50S gasser)

I am posting this to see if this happens on others or any good solution like resetting ECU.
 

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Funny. My car just hit 5k miles and feels like it really wants to run. Might just be me but my car seems to get smother and quicker with more miles..
 

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Discussion Starter · #4 ·
Go turn off the Eco Pedal. That was the reason behind my Q50S being slow. The pedal would stop going down!
I don't have eco pedal.
I had it running fine before..... Just wonder it has something to do with ECO before I reset it. I don't like resetting ECU because all my setting will be gone and I have to redo it again.
 

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Discussion Starter · #5 ·
Actually I found out the reason for it. It seems while cruising @35-45 in traffic hwy, I found my gear was a little high. So when the road clear up, to get better steam, I downshift the gear. It seems that the car is learning my driving behavior to save gas by going to higher gear quickly. I am just speculating here. Is this true? if it is, does resetting ECU work?
 

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its possible. did you abuse the car in the first 1000K? be honest.
which fuel grade do you use?
any aftermarket installs?

delay can be from the tranny too. also possible if the dealer used conventional oil.
 

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Might as well give it a try.
Any chance it's your transmission shift points as well?

My impression was the ECU curves things based on the run factors of your engine (like gas quality, air/fuel ratio, etc).
And the TCM adapts the transmission to your driving habit.

I haven't heard of an ECU limiting gas or anything like that.
But who knows.. tech keeps evolving and changing.

Make sure you use the highest octane gas available as well.
Hopefully you are.
That may effect performance.
 

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Discussion Starter · #8 · (Edited)
its possible. did you abuse the car in the first 1000K? be honest.
which fuel grade do you use?
any aftermarket installs?

delay can be from the tranny too. also possible if the dealer used conventional oil.
Unleaded premium (92 I believe)
The first 1000, I drove it slow (below 4K rpm). I did 0-60 (automatic/sport).
no aftermarket other than accessories like LED lights, etc)
Again, it is the gear that I was wondering that Q50 sets it to 6 or 7 while driving at 35-45 mph.
I got conventional oil because it was first free maintenance.. I have to pay $89 for synthetic. I thought it does not matter since I am planning to replace them at 10K with synthetic.
 

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Discussion Starter · #9 ·
Might as well give it a try.
Any chance it's your transmission shift points as well?

My impression was the ECU curves things based on the run factors of your engine (like gas quality, air/fuel ratio, etc).
And the TCM adapts the transmission to your driving habit.

I haven't heard of an ECU limiting gas or anything like that.
But who knows.. tech keeps evolving and changing.

Make sure you use the highest octane gas available as well.
Hopefully you are.
That may effect performance.
Hey Andrew,

As u know, Palo Alto roads are hilly and usually after red light, when I turn left, the road is going up , I noticed the gear is a bit higher and when I shift down, it went to 3 or 4 so I am assuming it was higher than 4. So shifting to 3 or 2 does give me a kick.
I will give take off the negative over night. I just hate to set everything again!
 

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If you're using synthetic, you should be fine. If premium unleaded, you check out good.

I am guessing the only two reasons that it can cause the problem. check all lines around air intakes, possible power loss there. definitely not the transmission, too early, unless abused. I assume it is the ECU. Visit the dealer, tell them you have odd power loss and response delay. They shouldn't give you a hard time about it. It's all warranty covered.

Let me know how it goes. Good luck.
 

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This "issue" occurs on the G37 as well....considering they share the same drivetrain, its probably the same thing.

Although I heard it was more refined for the Q50, the 7 speed AT is known for lagging and being in too high a gear. Those of us that end up in city traffic (instead of mostly highway) seem to experience the issue more than those who dont.

I really do think its the computer "learning" your driving habits, its just not smart enough to realize you WANT to drive spirited but cant because everyone else is in the way :)

The fix for my G has been the ECU reset and then go drive "spiritedly" for a bit. Ive also noticed some success if I start driving in DS most of the time (not shifting with paddles, just put it into DS and drive it like an automatic). It seems to tune DS mode to be better than D.
 

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Discussion Starter · #13 ·
This "issue" occurs on the G37 as well....considering they share the same drivetrain, its probably the same thing.

Although I heard it was more refined for the Q50, the 7 speed AT is known for lagging and being in too high a gear. Those of us that end up in city traffic (instead of mostly highway) seem to experience the issue more than those who dont.

I really do think its the computer "learning" your driving habits, its just not smart enough to realize you WANT to drive spirited but cant because everyone else is in the way :)

The fix for my G has been the ECU reset and then go drive "spiritedly" for a bit. Ive also noticed some success if I start driving in DS most of the time (not shifting with paddles, just put it into DS and drive it like an automatic). It seems to tune DS mode to be better than D.
I haven't reset it yet because I don't want to re-program everything and things are still the same.
However, the good news is that, there is always Sport mode and my standard becomes ECO mode that tries to save gas by shifting the gear higher.

I figured that because I used to have G37 before but I thought that Q50 is more refined. The traffic is bad these days around this area so I will reset it maybe later in summer. Oh yeah..I also notice that when the engine is just warming up (cold start), I sense the throttle is holding up too. I am not sure if this is caused by my conventional oil that takes longer to warm up and lubricate the engine. It has been really cold lately too.

Thanks for confirming.... if G, I would immediately reset it but I just need to see if happens on others ;) Good thing I have paddle shifter to DownShift if I need power immediately.
 

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There is actually a way to do it without disconnecting the battery. The process is pretty well documented (just Google G37 ECU reset).

People have chimed in saying its the same process all the way back to the VQ30 engines in the Maxima and i30, so my guess is its probably still valid for the Q50 as well.

Throttle "holding up" might not be the engine as much as the transmission....it seems like the transmission computer keeps the car in lower gears longer before the fluid warms up. It should stay in lower gears longer ALL the time as far as Im concerned :) but I think the initial driving when cold is more transmission related than oil.
 

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Discussion Starter · #15 ·
That's what I thought... just trying to get some knowledge with Q50 since it is new and haven't had much change to look into it.

Yes I am aware that method. The timing is killing me.... I never got it right back in G... I guess I am quite impatient!!!
 

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Discussion Starter · #16 ·
just update: It seems it is normal now! I discharged it last night and drove it this morning to work. I did not try to reprogram it by driving spiritedly but I seems it is back to normal (not eco mode on standard)
 

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They all do that. It is a by product of the RE7's deault eco programming. However in most real world applications it requires more throttle input...which actually hinders economy.

The Q is miles ahead of the first few cars that came out with that transmission as far as detectable lag is concerned but it still tends to settle in to some bad habits over about 5k, which is really overkill because the car will end up at the same place no matter what.

I reset my idle using the computer every oil change or so, but in the mean time I almost always drive in Sport mode. This will typically hold the gear longer and will always require less throttle input to overcome. It completely resolves the sluggishness.
 

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Ive always wondered that about the 7AT....it drops into high gear way too early, presumably for mpg reason. But if I need to accelerate it bogs so much in that high gear it HAS to be using more fuel than just being in a lower gear to start.

And oddly enough, running in DS, my mpg doesnt suffer much, if at all.
 

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Ive always wondered that about the 7AT....it drops into high gear way too early, presumably for mpg reason. But if I need to accelerate it bogs so much in that high gear it HAS to be using more fuel than just being in a lower gear to start.

And oddly enough, running in DS, my mpg doesnt suffer much, if at all.
I think there is a place where it is not a hindrance but right around that 35-45 mph range it settles in.

I have been instructing owners with JX35/QX60s to take the vehicle out of eco mode for in town driving and they are usually impressed with the economy changes. They often pick up 2-5 mpgs and say the vehicle feels much more fun.

The car is seeing your throttle input as a load request switch not a physical throttle cable (like the stone ages), so there is ability to modulate what happens when the throttle is depressed. To me the best example of that is taking off from a stop light in a newer bmw, to me there is a significant delay while the car works out what it feels like doing.
 

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I think there is a place where it is not a hindrance but right around that 35-45 mph range it settles in.

I have been instructing owners with JX35/QX60s to take the vehicle out of eco mode for in town driving and they are usually impressed with the economy changes. They often pick up 2-5 mpgs and say the vehicle feels much more fun.

The car is seeing your throttle input as a load request switch not a physical throttle cable (like the stone ages), so there is ability to modulate what happens when the throttle is depressed. To me the best example of that is taking off from a stop light in a newer bmw, to me there is a significant delay while the car works out what it feels like doing.
I don't quite iunderstand: you pick up mpg if you drive in Standard/Sport in city traffic over ECO? I thought city driving is where ECO is most useful.
 
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