Hey guys, Recently, my 05 G35 5AT sedan's rpm when downshifting/upshifting started to stutter. What I mean by this is that during MANUAL MODE driving, when I upshift, lets say from 1st to 2nd, the way the rpm "rev matches" jerks. There isnt a smooth transition anymore. I left the car in "D" mode and it still does it, except since the car auto shifts at very low rpms i couldnt capture it as fast. I called my local infiniti dealer and they said that there isnt a problem and that during manual mode the rpm does drop when shifting (duh!) but, the WAY the rpm drops is whats confusing me. I have taken a video, but I am not sure how to post it on here since HTML code is off. Along with the random rpm jerkiness, theres also a whine that comes with the jerk now on HOTT days (currently days are 95F+). This also happens on upshifts.

If there's anyone with any info on this problem etc, it would be much appreciated. BTW, the car has approx 87k miles and transmission fluid was swapped at 49k. Im just not ready to pay the dealer $x until I know for sure what the problem Is.

Thanks

 

fluid flush, add external cooler. check out CIN motorsports since u are in charlotte

 

upload the video to youtube and link it here.

 

Videos from youtube:


http://http://www.youtube.com/watch?v=nW_jpw8bj2g&feature=youtu.be

http://http://www.youtube.com/watch?v=huDjUyKYB_A&feature=youtu.be

http://http://www.youtube.com/watch?v=f6uRSt2Xo_k&feature=youtu.be

 

If the Tach is jerky, yet the engine is smooth.......i would say the tach is going bad, RPM signal wire is bad, or the crank angle sensor is going out. A bad crank angle sensor will make the rpms jump a little and cause long starts.

 

Dealership found out problem...Apparently the tachometer is broken...they're going to replace the entire cluster if warranty goes through...its close to a $1000 repair (w/o warranty).

 

how does a bad tach cause stuttering during shifts?

 

its also the Transmission...i know its a year later that I'm responding, but after the tach replace, the car was fine..but recently, after a Fluid flush, the car has been throwing rough shifts through each gear in D more when the car is cold. When the car is hot, and its hot outside, and im in Manual mode (99% of the time), I can feel the rear axle of the car jerk (A bang sound) and then the gear changes...So, I dont know whats going, but my warranty Expires in November, so Hopefully if my transmission is bad, i can get it replaced.

@CLyons0203

Its the bad tach not syncing properly with the gearbox and the ECU..basically confusing it (was told this by infiniti mechanic)