Stormy21

I bought a 2020 RDX Advance a few weeks ago and love it!... EXCEPT, when I brake and then punch the gas, there is a FULL 1.5 SECOND DELAY. Even in Sport+ there's way too much delay. It's soooo annoying. My 2016 Subaru Forester never had this issue. I hope Acura can fix it with an OTA update. Other than that, it's darn near perfect (besides needing ~70 more hp

Funz51

suggestion,
1) ecu reset, search on this site for details
2) a hondata or ktuner tune, search on this site.

#1 is free and may really help a lot.

ie:
1. Depress the throttle pedal all the way in, with ignition/accessory off. Then, turn on the car to ignition mode. (Hit start twice without foot on brake)
2. Keep pedal down until the check engine light disappears. It took about 20 seconds.
3. Power down the car to off state. (Hit start button once)
4. Press brake pedal and start the car normally by pressing the engine-on button.
5. Procedure is completed,

russianDude

Does Ktuner/Hondata really help with the hesitation delay? I’ve seen mixed responses from it being the same or making it slightly better?
I will try ecu reset you mentioned

Funz51

i think the ktuner helped my delay. did not fix it completely. the ecu reset fixed it completely, for the time being.

Funz51

ok,
just for a test, I removed the ktuner tune and burned the stock profile.
I found that the throttle delay is there for sure.
I did the ecu reset, and I found that upon light touch, it was responsive. but upon a punch of the throttle, the delay was definitely there.
So I cannot say that the ecu reset will solve the delay issue with stock.

With the previous Ktune Stage 2, I felt no delay at all, under any conditions.
I will be burning back to stage 2 in a week or so, so can test again then.

russianDude

thanks for the info!

russianDude

If delay can be fixed with software, why no update from Acura? Is it some government mandated feature to save gas or the software is protecting transmission from sudden torque?

Burger Steak & Eggs

I'd guess the latter, and maybe a bit of emissions reduction too. I don't care, I want it gone.

Wander

I'd guess emissions, fuel economy, AND protecting the transmission. If Acura did anything to compromise the first two after sale, the proverbial $hit would hit the fan.

Dereileak

your not doing a ecu reset, your doing a pedal calibration

Funz51

That's not how I have seen it referenced, but Ok. makes sense.

Jaco

iTrader: (1)

Had this same thing with my 13 TL, I called it the rolling the stop sign fail made by Acura. Every time you slow it has to downshift from 3rd to 2nd at the time (6 Spd AT). Good to learn it exists in the RDX.

DJA123

I believe this problem began when "traditional" 4, 5, 6-speed transmissions were cast aside in favor of new, more efficient, logic controlled CVT/high gear count automatics. Instead of straightforward load, rpm, throttle position shift parameters, we now add decision-making and ratio options that are a magnitude beyond 6 speeds. Real-time PCM analysis manages every action in a modern transmission. That logic is hamstrung by prioritizing fuel efficiency, plus the extreme complexity of managing all those "gears" in real world driving.

The focus of this thread could easily be the CVT in my wife's Subaru. The hesitation from that demon spawn - when forward movement is a safety requirement - is without question the worst of its many faults. Hesitation when moving into faster moving traffic is not just annoying, it's dangerous. It just seems there are too many factors to be analyzed when a basic function of an automobile is requested by the driver. This problem is certainly not unique to this vehicle. But regardless of the technology, or brand or class of vehicle, hesitation is undoubtedly causing harm. Damn the fuel economy if people are being creamed while holding their foot to the floor.

ESHBG

https://www.carcomplaints.com/news/2...-lawsuit.shtml

ACURA MDX AND RDX ACCELERATION PROBLEMS CAUSE LAWSUIT

Class action says Acura MDX and RDX vehicles hesitate, shift into NEUTRAL and stall.

Graphic-er

I read about that yesterday, but didn’t see any detail about the hesitation issue in this thread. The lawsuit is about the ecu freaking out at highway speeds causing massive deceleration and response issues.

Rocket_man

"... The plaintiff says he was driving on a highway in March 2020 when the MDX suddenly decelerated from 75 miles per hour to 45 mph on two occasions in about 20 minutes. He says he took the MDX to a dealer but was told there was nothing wrong with the vehicle, so no repairs were performed.Later that month the MDX allegedly decelerated to a stop without him touching the brake pedal. The plaintiff says he took the SUV to a dealer but no repairs were performed because technicians said nothing was wrong with the vehicle."

Classic Acura.... 'nothing wrong here, nope, never seen that before, the car was designed to do that' Acura has given themselves a very bad reputation. Just fix your damn cars Acura! While you still have people willing to buy them.

russianDude

I read the lawsuit, its about limp mode for most part, not hesitation during acceleration. We dont see many limp modes (if any) for 2020 RDX.

Wander

https://acurazine.com/forums/3g-rdx-...9-spec-971802/

Anyway, I think the lawsuit touched on hesitation during acceleration AND "limp mode" situations. But it's pretty darn light on detail.

Maybe the lawyer(s) are sourcing it from the experts at AcuraZine?

russianDude

Nothing about 2020 RDX? Or its small number ?

Wander

Forgive me if I neglected to sift through all 360 posts in that thread. Are you aware of fundamental engineering changes between 2019 and 2020? Please share.

russianDude

no, not aware. Acura would not necessarily tell us if they changed/redesigned some electronics to address the issue. Especially if there is a lawsuit now, you won’t hear anything from them

Wander

Seldom do hear anything. Until the mid-cycle refresh, when they will advertise "enhanced responsiveness of the state-of-the-art transmission".

That's pretty much exactly what they did with 3rd-gen Pilot at mid-cycle, after similar drivability issues which AFAIK remain unresolved for previous model year vehicles. Like the one I traded for 2019 RDX, expecting a vastly improved driving experience.

Acurafangrl

Hi all, new to the forum. Just got my first rdx last week (actually it's my first Acura). Love the car, but I definitely don't love this issue. I noticed it the other day when I was changing lanes. I slowed down quite a bit (but did not come to a full stop) while waiting for space to open up in the lane. I thought I had enough room to change, but also saw there was a car trying to speed up from behind in that lane (gotta love nyc). I went for it anyway, thought it was enough space and time. Jerk kept speeding up as I was mid lane change. I tried to accelerate in order to complete the change asap, but it took forever!! When the car finally accelerated, it basically just jerked forward. Luckily I made it in time, but this should not have happened in the first place. I was driving in comfort mode. Does this happen in sport mode as well? I remembered reading that it didn't, but not too sure

anoop

There is no way to get rid of this problem other than to drive a little more gently. In other words, don't attempt any close call type maneuvers that require sudden acceleration.

I have literally skipped lane changes and done u-turns just because I know what kind of feeling arises within me especially if the person in the other lane isn't being accommodating. When trying to change lanes, I turn on my indicator. If the person in the other lane looks like they are going faster than me and doesn't slow down, I patiently wait for them to pass rather than trying to speed up and get in.

My driving fun karma for this lifetime ran out when my BMW E46 got old, but I had a lot of fun with that car.

DJA123

Long thread = much speculation/theory/opinion. Since most (all?) here are not Honda powertrain engineers, that's all we can do.

Just to pass the time in lockdown, do a Google search for "[Brand] acceleration hesitation". As you might expect, this not a problem unique to Honda/Acura. You will find significant discussions from across the industry. By scanning those threads, I found comments and speculation that could be a copy/paste from here. MBWorld thought it might be hill-holder function; AudiWorld thought it was ECU logic; Volvo Community thought is was a software issue, etc. Same stuff. I can also add my wife's Subaru to the discussion.

I'm also not a Honda engineer, so here's my speculation/theory/opinion: Newer, high gear count transmissions, under PCM control, have a LOT of things to consider at sudden power demands. Couple that with the mechanical requirements of dropping 3, 4, 5 gears, PLUS turbo lag in our case, and now we're surprised by a delay? I believe manufacturers HAVE to be aware of this and would eliminate it if possible. But the need to hit fuel economy numbers while making cars more powerful is a devil's bargain, and driveability is the sacrifice.

Carry on...

anoop

This is also something that would be hard to discover on a test drive because I wouldn’t want to push the engine in this way before break in.

quantum7

I wouldn't want to push MY car before break in, but I definitely would drive my test drive car they way that I would or may have to drive on my daily commute. This is one of the reasons why I drop the TLX from consideration very early on. The ZF9 did so much gear hunting and delay downshifting when I demanded power from a coasting roll that I knew I could never be happy with that transmission (therefore MDX, Pilot, Passport, etc were off my list).

That is also the reason why I ask for an extended test drive.....take the car for an overnight and drive my daily (100 mile) commute. I don't go out of my way to beat on the car, but I drive it as I would everyday, and put it through how I might have to drive it.

I am sure test drive cars get plenty of non ideal break in mileage.

Acurafangrl

Sorry for my ignorance, but isn't break in no longer recommended for new cars these days?

acuraada

It's actually less for modern day cars. I owned a BMW before and have always found their recommendations to be sound and logical, applicable across brands.

Link here https://www.bmw.com/en/automotive-li...a-new-car.html
Looks like its updated recently too...

The right way to break in a new car

Many drivers wonder whether breaking in a new car is still necessary or if this practice has been superseded with the advances in technology. The answer? Yes and no...

Doing an engine break-in used to be a standard procedure with new cars. And it’s still the case that you should avoid running the engine at high RPM for the first 1,300 miles. Experts recommend a maximum 3,500 rpm and 90 mph in diesel models and 4,500 rpm and 100 mph in gas models. This will give the engine and transmission sufficient time to adjust to each other. Once you’ve reached the 1,300-mile mark, you can gradually increase your speed and your engine’s RPM. In particular, avoid to put too much strain on a cold engine. However, that’s true not just when breaking in a new car but for the whole life cycle of your car. Likewise, never turn off an engine that has been running hard. Allow it to cool down by driving a few miles at a gentle pace.

anoop

This is from the RDX manual:

"During the first 600 miles (1,000 km) of operation, avoid sudden acceleration or full throttle operation so as not to damage the engine or powertrain.

Avoid hard braking for the first 200 miles (300 km). You should also follow this when the brake pads are replaced."

Wander

And that's exactly what I did on my test drive and thereafter. NOT!

The throttle and transmission are more responsive in Sport IDS mode than in Comfort. And it seems to be best to really punch the accelerator when you need rapid acceleration, rather than gently depressing it. Otherwise it may pause, downshift, pause, downshift some more, OH CRAP! I recently found this to be especially true at high elevation, cuz you really need the turbo boost to make any power.

This may have something to do with the "adaptive" features of the transmission controller. If you drive like a granny, it will bias more toward smoothness of shifting rather than abruptness.

$0.02 based strictly upon seat-of-the-pants accelerometer. And occasional butt clenching!

anoop

Perhaps the solution is to go electric, or try and find an older engine like the one in the MDX, to avoid this problem.

Taz69

Here is what it is. You are correct on the throttle lag. Manufacturer calls it torque on demand. But it is anything but. Hyundai, Acura, Kia, just to name a few all do it. If you hook up a scan tool to the vehicle and watch what happens its crazy. My wifes Santa Fe sport and I see Acura RDX do it. You will watch your throttle pedal percentage go up but nothing happens at the engine. Hyundai has a .6 to 1 sec delay before the engine does anything. With drive by wire they have screwed with the programming. Its way worse in the SUV for the same manufacturer than it is in the car of the same make with the same engine and transmission. They put it in the because these small 4 cylinder turbo can make peek torque as low as 1,600 rpm. So in a front wheel drive SUV it can be a lot easier to unload the inside front tire and get the wheel spinning. Taller heavier vehicle you can start to spin the tires. So I think for older folks or whoever they intended it for the vehicle will not let the engine come on at the same time with the pedal. I hate it.. Its bad between 5-20 mph. The Hyundai gets even worse if you are turning it senses the wheel and if you are turning on to a side street or a 90 degree turn its bad.

Taz69

Thats why the same engine and transmission thats in the Accord and in the RDX the car folks dont feel it that much or at all. Its not the transmission but programming to the engine and a big delay or very soft opening to the engine. You can watch it on a scan tool or with k-tuner. You can see what the pedal on the floor does and the engine is way behind.

Wander

This makes sense because in the winter I noticed that the delay was especially bad when turning from a snowy side street onto dry highway. At the first hint of wheel-spin during launch, while turning the steering wheel, it was like the engine just shut down. Damn cars are trying to be way too smart. Kinda like a recent Boeing passenger jet.

Pretty stupid if they are programming the same for FWD RDXs and SH-AWD equipped models.

Funz51

Yes, you can get around it. tap a paddle just before you accelerate. it has worked for me now, and before my ktune.

anoop

It takes a while for the gear change to even register. Everything in slow motion.

Madd Dog

Break-in suggestions only apply to those who buy. It is waived for those who lease.

Funz51

I have always felt that the paddle gets the tranny’s attention so to say. It is just another input to the decision making of the ecu. You can also try that aforementioned throttle reset. Look for it earlier in this post.

Wander

I say break it in like an old-school cowboy. Show it who's boss.

Get a car that's built for it, and you can whip it hard for a long long time. Get a rickety econobox and it will be whimpering at roadside in a month. ( Honda is a motor company first, and a car company second ).

But don't neglect basic maintenance! ( I'm looking at you, BMW! )