Nissan 370Z Forum - View Single Post

kball5 · 06-01-2016, 10:27 AM

So I've got some weird issues with my 7AT. Let me begin by saying this issue has progressed over time, when I first bought the car last November none of these issues existed. All I do is daily drive the car, and I don't push it extremely hard. I would call it 40% spirited and 60% casual commuter.

These problems are not as bad when I first start the car. In fact if they are very bad mid drive I can turn off the car and immediately start it to relieve some of them. I was also able to improve them slightly by unhooking the battery overnight to reset the ECU (and I assume TCU?).

Issue 1:
Torque converter randomly unlocks while in Manual Mode. Sometimes I can be in 5th gear on throttle, let off and nothing happens. Other times it'll unlock and revs will drop from lets say what they should be ~2700 to 1000. Then to get the torque converter to re-hook I have to get back on the gas, it'll rev to like 3500, hook and then grab at 2700. Resetting ECU reduced this problem a lot. However, in 3rd gear the torque converter now ALWAYS unlocks when I get off throttle. It never holds revs anymore (it use to).

Issue 2:
As of recent there is significantly more rev flare and lag between gears than I am accustom to. When shifting, previously, the shifts were semi fast and usually fairly firm. Now they are nothing more than mushy and laggy. Keep in mind this is manual mode and these comments are based on fairly casual driving at ~20% throttle. These issues are far less noticeable at 75%+ throttle. (Also slightly relieved this issue when the ECU was freshly reset. Has gotten slightly worse after 100 miles of driving)

Issue 3:
Occasionally when shifting from 3rd to 4th gear the car rev-matches like I'm downshifting. Weird as heck.

Issue 4:
In automatic mode (normal D) the transmission would very often upshift when I get on throttle instead of downshifting, dramatically bogging the car down at like 1100rpm on heavy throttle. I believe this issue has also been reduced drastically since ECU reset.

Has anyone else had these problems or similar problems? Trying to get a better idea of what is going on and what to do before the dealership tries to tell me I need a new transmission. My 2011 is out of the 6year powertrain warranty as of March. As some of these issues have been at least somewhat relieved by resetting the ECU, could that alone be the problem or is there an actual mechanical problem here?

06-01-2016, 10:27 AM	#1 (permalink)
kball5 Base Member Join Date: Oct 2015 Location: Georgia Posts: 10 Drives: 2011 370z GM ST A7 Rep Power: 10	Weird Issues With 7AT So I've got some weird issues with my 7AT. Let me begin by saying this issue has progressed over time, when I first bought the car last November none of these issues existed. All I do is daily drive the car, and I don't push it extremely hard. I would call it 40% spirited and 60% casual commuter. These problems are not as bad when I first start the car. In fact if they are very bad mid drive I can turn off the car and immediately start it to relieve some of them. I was also able to improve them slightly by unhooking the battery overnight to reset the ECU (and I assume TCU?). Issue 1: Torque converter randomly unlocks while in Manual Mode. Sometimes I can be in 5th gear on throttle, let off and nothing happens. Other times it'll unlock and revs will drop from lets say what they should be ~2700 to 1000. Then to get the torque converter to re-hook I have to get back on the gas, it'll rev to like 3500, hook and then grab at 2700. Resetting ECU reduced this problem a lot. However, in 3rd gear the torque converter now ALWAYS unlocks when I get off throttle. It never holds revs anymore (it use to). Issue 2: As of recent there is significantly more rev flare and lag between gears than I am accustom to. When shifting, previously, the shifts were semi fast and usually fairly firm. Now they are nothing more than mushy and laggy. Keep in mind this is manual mode and these comments are based on fairly casual driving at ~20% throttle. These issues are far less noticeable at 75%+ throttle. (Also slightly relieved this issue when the ECU was freshly reset. Has gotten slightly worse after 100 miles of driving) Issue 3: Occasionally when shifting from 3rd to 4th gear the car rev-matches like I'm downshifting. Weird as heck. Issue 4: In automatic mode (normal D) the transmission would very often upshift when I get on throttle instead of downshifting, dramatically bogging the car down at like 1100rpm on heavy throttle. I believe this issue has also been reduced drastically since ECU reset. Has anyone else had these problems or similar problems? Trying to get a better idea of what is going on and what to do before the dealership tries to tell me I need a new transmission. My 2011 is out of the 6year powertrain warranty as of March. As some of these issues have been at least somewhat relieved by resetting the ECU, could that alone be the problem or is there an actual mechanical problem here?