Honda and its luxury division Acura are brands known for reliability and excellent build quality.
But, it doesn’t matter who has built your car, as Honda DCT transmission problems are something you will experience at some point.
The most common Honda DCT transmission problems are slow acceleration, the transmission feeling like it is stuck, rough shudders and vibrations at low speeds, and transmission shifts to neutral during a drive.
Honda’s DCT system is considered to be among the most reliable in the whole car industry, but it doesn’t mean that it is also free of any problems.
Some are caused by user errors and unfamiliarity with dual-clutch transmissions and their peculiarities.
At the same time, others are caused by design defects.
What Is Honda DCT?
DCT stands for Dual-Clutch Transmission, and it is, for all intents and purposes, an automated manual transmission that uses two clutches to engage gears. One clutch for odd gears and one for even.
Honda has three models of DCT transmissions, a 7-, 8-, and a 9-speed version, which is available on different models of their vehicles.
Because these transmissions are automated, owners usually confuse them with regular automatic transmissions.
This can be a source of many assumptions and actions that can cause improper function and damage to the transmission.
This is usually caused by the fact that DCT doesn’t have a clutch pedal, just like automatic transmissions.
But, they do not need to have it because of how two clutches are constructed, and for one clutch to engage the gear, the other must disengage its respective gear.
Most Common Honda DCT Transmission Problems
The most common issues with Honda’s DCT system can be traced to the improper operation of the dual-clutch transmission in the manual gear selection mode.
Users often presume that it functions similarly to automatic transmissions and expect it to behave similarly under certain circumstances.
But, wrong assumptions produce unexpected results.
Hesitant operation of down or upshifting and certain jerkiness while driving at low speeds in low gears were caused by slightly off programming of the transmission shift pattern.
In comparison, some problems were caused by the improper design of the wiring harness.
The surprising thing is that most of these problems are present on all of these three transmissions.
So, let’s get to their details and how to fix them.
Slow Acceleration
Imagine a situation where you are trying to make a turn onto a highway, and you see that incoming traffic is far away that you can safely accelerate.
You are in the 2nd gear, and you step on the accelerator, but nothing much happens, and the vehicle starts accelerating very slowly.
This creates unexpected and potentially dangerous situations when merging into the highway traffic, as you could do it too slow and risk being hit by the oncoming traffic.
This problem is specific to the models with 8-speed DCT, which feature a torque converter intended to smooth out vibrations in the lower gears.
The cause of this is that the clutches of the torque converter are not adequately “broken in,” but also specific settings in the Powertrain Controle module (PCM).
This is something you have to take your vehicle to a dealership, as it requires an update of PCM settings and performing the break-in procedure on the torque converter.
The Transmission Feels Like It Is Stuck
Arguably the most common problem with Honda’s DCT is the feeling of the transmission as if being stuck between gears when trying to accelerate. Some owners describe it as a transmission slipping.
But the symptom is that the engine revs, but there is no increase in power reaching the wheels. This problem almost exclusively happens in cold weather.
Though many Acura owners think that this is a design flaw and problem with the DCT system, it is actually a user error.
Honda did provide a transmission programming update that generally makes it go away, but it doesn’t fix it.
The problem is that, like any other piece of machinery, DCT has to be warmed up in cold weather before it can work optimally.
The real cause is that people would turn on the engine and step on the accelerator in cold weather.
The proper solution is to operate your vehicle as it should be in cold weather.
Start the engine, wait for 10 to 20 seconds for the fluids to start warming up and flowing, and then step on the accelerator.
Rough Shudders and Vibrations at Low Speeds
For many owners of Acuras with DCT, very early in the life of their vehicles, very annoying shudders and vibrations develop when driving at speeds under 40mph or when standing in traffic.
It is most pronounced when the engine is below 2,500 RPM.
Most commonly, this is caused by a problematic torque converter combined with drivetrain programming that keeps the transmission in too high gear, usually 4th.
It leads to the torque converter locking up and causing very annoying vibrations.
This can be solved only by replacing the torque converter.
Transmission Shifts to Neutral During a Drive
When driving an Acura with a DCT system, one potential problem is that it can suddenly shift to the neutral.
This can be a hazardous situation as you lose the vehicle’s ability to accelerate. There are two potential causes of this issue.
The first one is the more common and can be accompanied by the car shutting itself completely when coming to a stop.
The cause of this is the faulty shift solenoid and potentially also the transmission fluid contaminated with dirt.
And to fix it, you have to replace either just the solenoid or also the transmission fluid.
The second probable cause is the transmission wire harness design issue, present on other Honda, Acura, and some FCA transmissions.
The crimp connectors are not properly designed by the harness supplier, which can lead to a sudden shift into neutral.
The solution for this is to replace this harness with an improved design.
On Which Honda Models Can The DCT Be Found?
Honda’s DCT transmissions are not very common in their models. They are exclusive to some Acura models introduced after the 2014 model year.
The sole Honda badged model with a DCT system is the second generation of the NSX model, which is in North America marketed under the Acura brand and features a 9-speed DCT transmission.
Other Acura models with DCT are the first generation of TLX, but only the models with 2.4-liters inline-4 K24W7 engine, ILX models with the 2.4-liters inline-4 K24Z7 and K24V7 engines.
All of these came equipped with an 8-speed version of the DCT transmission.
Also, the hybrid versions of RLX and MDX models launched in 2014 came with the 7-speed version of Honda’s dual-clutch transmission.
Conclusion
Honda’s dual-clutch transmission is an automated manual transmission that uses two clutches for engaging the gears.
It has debuted in the models introduced in 2014 as an effort to produce a more economical driving experience but with driver engagement similar to the manual transmission.
It exists in three versions with 7, 8, and 9 gears, but all of them can potentially suffer from similar issues, and these Honda DCT transmission problems have the exact causes and fixes.
Sources
https://acurazine.com/forums/4g-tl-problems-fixes-297/torque-converter-shudder-911053/
https://www.tlxforums.com/threads/2015-acura-tlx-8-dct-issues.23233/