[Mrcole]

I just want to say I'm glad I'm not going crazy and this is happening to others as well - Now to figure out if it is truely a problem we should be worried about.

 

[GWHayduke]

I've noticed this too with the volant, just thought it was normal. Anyone else notice this? I can almost feel a little surge when slowing down to stop, had to hit the brakes a little harder a few time because of it too.

Yes, a little surge while slowing down to stop. That's exactly how I would describe it.

 

[alkeli]

Well then, that could be a couple of things. Yes, the torque converter lock could be sticking, but it should also only be engaging when you've been cruising at highway speeds for a while. Don't know the specs of how fast or how long though... So the engine gives a bit of gas when the rpm's drop too low. Could also still be something to do with a sensor not reading idle speed, throttle position, rpm's or airflow properly, so when the rpm's drop to a point, the ecu kinda panics and gives it a bit more gas to keep from stalling.

Again I'm referencing older engines, don't know everything about the X's engine...
Posted via Mobile Device

 

[satown210]

Mine started doing it after I disconnected the battery. When I am decelerating I feel engine breaking slowing me down. Then is seems like I can feel it downshift to 1st. It suddenly gives a little push when almost to a complete stop making me brake harder.

 

[Mrcole]

So -

it seems like this has happened to multiple trucks during different instances i.e. it has happened to stock trucks with no alterations, after an ECU reset, after a TB cleaning & after a Volant install. Kinda hard to say what is causing the problem or where it is stemming from. Anyone near me (Indianapolis, IN) that is experiencing the same thing or not?

 

[mahnaymisjay]

Mine does that when i let off the gas pedal after a moderate acceleration or if let off the gas going down hill. Thought it was normal. Doesn't seem to affect the ride no deceleration when it happens. It is a new truck shouldn't have any problems right??

 

[Mrcole]

This is what I am trying to figure out - if it is in fact normal or not. By all means to me it does not feel normal. some of us have noticed it after some driving, some after a modification. I wonder if someone can chime in and verify there truck is not acting in this manner. I've heard some say that their trucks don't do this but nothing concrete. I still haven't been able to make it out to test drive a 2010 and find out for myself.

 

[skibum315]

Well, I can verify that my '08 doesn't do it ... but I've got a manual, so that's probably not very helpful.

 

[Mrcole]

Didn't you see the sign on the door? "No Manuals Allowed!" :iconbiggrin:

Just kidding - this is still good information to have.

 

[satown210]

Mine has smoothed out some but it was definitely noticeable immediately after disconnecting the battery. It still does it every once in a while. I noticed if you throw it in neutral while driving and then back to drive it seems to get worse until the next ignition cycle. I was trying to figure out a noise once and put it in neutral and killed the engine while driving. I lost overdrive until the next ignition cycle. To me it seems like it is a software issue.

 

[Mrcole]

Yes,

I am starting to lean towards a software problem or a sensor/way software interprets a sensor problem.

 

[alkeli]

Sensor... isn't that what I said before? lol

 

[satown210]

Sounds like it's not a fault rather a bad design or bad way the transmission is interpreting inputs.I have not noticed mine doing it in a while.

 

[Mrcole]

Anyone had a chance to test a 2010 X and see if the problem is there? The next thing I think I'll do is swap the TB with one from a different X....when I find one.

 

[jeff_redx]

My 09 auto doesn't exhibit any of the peculiar oscillations of the engine or tach in the 30 to 45 mph range.

 

[Mrcole]

Thanks for the info. I should be getting a new TB soon and let you know how the swap goes.

 

[satown210]

i noticed mine, if it does it, is always around the 40 mph area

 

[mahnaymisjay]

Found a video on youtube of an X doing a tach bounce it happens towards the end of the video.

http://www.youtube.com/watch?v=nq8oT1Z_tgU

 

[jeff_redx]

Video was of a 6 speed X. Looked more like a down shift to a lower gear. Not the same thig people are experiencing with auto trans.

Jeff

 

[tarfu]

when i took my stock S to the dealer about 2 mo ago they tested 'everything' including the 'alpha' whatever that is. they found nothing mechanically or electrically wrong w/the vehicle, no leaks, no transmission+cooling leaking/mixing. they let me road test an 08 frontier. after the engine warmed up, the truck exhibited the exact same qualities after letting off the pedal around 40mph. the shop mechanic i rode with encouraged me not to drive like such a pu$$y and to 'get on it' more often. this is a tradeoff between owning a lot of XOM and owing a lot because of XOM. I prefer the former.

the dealer said not to touch the throttle body. something about 'drive by wire' and if i opened it up not only would i break it but the 4 horsemen would suddenly pop out of my microfilter and eat me. needless to say, i haven't messed with it.

my mpg isn't affected by this tach drop. truck still 'feels sluggish' on standing/rolling starts. this problem cropped up after 20 - 21k miles. it did not do this before.

with a 60k mile powertrain warranty, it's my hope any future problems which develop as a root cause of this issue will be taken care of by nissan. as i've registered these problems with a nissan dealer while inside of the full factory warranty period, i'll hope for more recourse than less should an issue develop. which i hope it doesn't. i've been satisfied to date with my x.