AT frs rpm issue
 

When you tap and let go of the throttle lightly, is it normal to see a drop in the rpm (below 500) and then slowly rising depending on how much you throttle you tapped? Is anyone else experiencing this issue?

Ive experienced this. I don't think its an issue per say... but I would think there are more knowledgeable people than myself that could say yes or no.

If I recall right mine does this but nothing to worry about its just the timing changing (well my guess)

@soulreapersteve @go_a_way1 Glad I'm not the only one but it's more noticeable when you are in P, N or accelerating from a complete stop. The weird thing is if you're in sports mode the problem goes away.

Only really happens when in N or P I always give it too much gas off the line to notice haha! It could also be the tranny moving the fluid around and probably has to do with the torque converter is another guess as to what it could be haha!

Was thinking this originally but didn't want to say anything since I know jack shit... :D

What year is your car if you don't mind me asking?

@FRSBRZGT86FAN Does this happen in your 2015 frs?

I drive a 2013 and according to @go_a_way1 status it looks like he has a 2013 too.

Yup I have a 13 :) It has done that idle dip thing since she was brand new. I have also had all the updates done but I am also ECU Tek tuned so that might overwrite the update changes :iono:

Mine is '13 MT and I notice it does this sometimes. When it does it, it keeps doing it. But when it doesn't, I can't recreate it no matter how many times I try. I've never worried about this, so I didn't mention this in this forum or to the dealer.

It used to when I first got it, however now after a TSB with a TCM logic reflash and with an OFT tune I've edited a lot I don't really notice it at all

Now that there's a TCM flash TSB, I wonder if any tuners can find out how to do that.

I thought that was only for the 15s?

Highly doubt the 15s have a different TCM than us.

Hmm I never had an issue so I never looked into it haha! I thought they had issues though on the 15's?

Yes, it's only '15 AT.
S-SB-0021-15

Sweet I was right haha! Thank!!

The TCM is exactly the same as the other years of AT FR-S however the new software referred to in the TSB is the latest logic for the TCM, think of it as a simple software update that corrects some screw ups. I was wondering as well if tuners can flash to the TCM. Paging @steve99

I am not aware of any tuning systems that flash the Transmission Control Module, all just flash the Engine control unit AFAIK.

Ecutek appears to be able to adjust the traction control parameters somehow, it may be just adjusting whats sent from ECU to the VSC or TCM modules.

Maybe talk to the moteast or deliceous guys

Their was some changes to the ECU firmware after late 2014 ,it appears to be due to changes to dash firmware/hardware so its possible their were also corresponding changes to TCM firmware.

This may mean that even though the TCM module may be the same hardware as in earlier cars if you managed to flash later firmware to it it may no longer communicate/interact correctly with the other control modules in the car like the Stability control/DASH/ECU or some other control modules of the earlier car

This is likely why that TSB is only for 2015 cars