Hey guys. I got an A/T Coupe. I installed the Invidia Gemini TD exhaust for a couple weeks and I recently notice that the car is running mostly at 4th gear on freeway - 80MPH at 3k RPM. The only way I can make it shift to 5th gear is to give it a hard throttle to bring the RPM over 4k but then the speed is now at least 90MPH. For engine mods, I only have Plenum spacer, Z-Tube, K&N drop in air filter and the exhaust. Plenum spacer is the last mod and it doesn't do anything to the gear. The problem occurs since the exhaust is installed.

Does anyone have the same problem? I am thinking to bring the car to a transmission shop but I would like to hear from members here first since we all have same car. Thanks for any input.

 

You sure? 3k RPM at 80MPH seems pretty normal.

 

have you done a ECU reset since installing your exhaust? if not reset it and see if it makes any difference.

 

I am sure 3k at 80MPH. I know that it is normal but then the gear is 4th gear. With the stock exhaust, it must be 5th gear at 80MPH.

Hmmm No, i did not reset ECU when the exhaust is installed but I did reset ECU after the spacer is installed. And it makes no difference except for the car is pulling harder and smoother.

 

Did you count the gears shifting? Just to make sure its not the actual gear indicator near the speedo thats off.

 

Actually, I do not count but I know that it is 4th gear because every time I give it hard throttle over 4k RPM, it shifts one more time and that last one is 5th gear. And I also bring it to Manual Mode while driving at 3k-80MPH. And it also says 4th gear but the strange thing is when I bring it to Manual Mode, the RPM jumps from 3k to 4k-4k5 but still 4th gear.

 

Correct me if I'm wrong, but I think you're mistaking 5th gear with 4th. From your original post you said that at around 80mph you are at 3k rpm (4th gear), but when you give it a bit more gas you are then at around 4k rpm (5th gear). What is actually happening is that you were at 5th gear at 80mph, but as you applied more throttle your car downshifted to 4th gear. Hence, your rpm rose to 4k.

Also, for our cars when you switch from automatic mode to manual mode, the transmission will automatically downshift for you. That is why you saw 4th gear displayed. I don't think you have anything to worry about.

 

When I am at 4th gear (3k -80MPH), if I want to shift it to 5th gear, I have to bring the RPM up to 4k and at that point, the gear shifts again and that last one is the 5th gear. I can feel it when it shifts from 4th to 5th.

 

What G GS said be correct.

If you are in D and are going 80MPH on the freeway, the car should already be in 5th gear. If you mash the throttle while the transmission is still in "D", the car will automatically downshift for you into 4th.

If you are in D and are going 80MPH on the freeway, the car should already be in 5h gear. If you switch to tiptronic mode, the gear will say 4th gear. This downshifting is done so that you can pass cars easier.

Making a video of it would help a lot, so we can actually see what's going on, because I'm getting confused.

 

I'll try to get a vid. I see how the transmission works when I switch from D to Tiptronic.

But I dont understand why I am in D and it will downshift when I give it a throttle?

 

It will downshift when you are in D and give it throttle because when you hit the throttle, the car thinks you want to pass somebody. So it downshifts to a more appropriate gear to get that power. In this case, that gear is 4th.

 

Ummmm what you're most likely feeling is torque converter lock-up. It's more apparent because you've got a loud exhaust. Do a Google search.

 

5th gear 80mph 3k rpms is 100% normal. Thats what I got.

 

There is a thread dedicated to RPMs at 80MPH. Unless you have changed your FD then you should be right about 3000K in 5th gear.


Everything else you are suggesting is normal operation for the transmission and is due to lock, slip, or slip-lock.

You probably think you are in 4th gear because its much louder, but that is also normal.