jperdoch

I have found that whenever I use the adaptive cruise control, as cars pass me and then then get back into my lane it seems like it ALWAYS slows my RDX. In addition to be annoying then everyone behind me goes out to pass and then when mine speeds back up, they get all pissed off at me. I know you can adjust the sensitivity but no help there either.

Anyone else find the same thing ??? Just curious

robnalex

We love the ACC on our new RDX, but I can see how it could be problematic in heavy traffic with lots of aggressive drivers. We just did a trip from Raleigh, NC to western NC and back, nearly all on I-40. I had the ACC set on the 2nd from the longest distance, and sure, there were leap-froggers, but this would happen even without ACC since I like to keep a comfortable distance from the car in front of me. With regular CC I have to be constantly adjusting the speed up and down, whereas ACC makes this unnecessary. I've found the ACC is pretty "smart" in that when another vehicle passes and re-joins the lane in front of me, it will not slow me down if it detects that the other vehicle is moving faster than me. Pretty cool.

Yotrek

That's how ACC works, so if you are facing heavy traffic, better don't use ACC..

mrgold35

I've found ACC works best with low to medium hwy traffic with long straight runs. Heavy traffic can make ACC difficult to use because it is always moving you further to the back of line allowing cars to cut into the gap in front of you. I've found keeping the ACC on the shortest interval, using the paddles to downshift to accelerate faster to ACC speed, and using the gas pedal when needed for faster acceleration to maintain the 3-5 second gap I prefer having between cars.

Sometimes I get stuck behind yo-yo drivers (single or group of drivers that speed up and slow down -10 to +20 mph above and below the posted speed limit CONSTANTLY). If the speed limit is 70 mph, I set the ACC to the shortest distance and set my speed to 75-80 mph. ACC slows me down maintaining my 3-5 second intervals AND ACC speeds me up faster to close the gap when they jump +10-15 mph for short bursts. A few clicks downward to lower my ACC speed when I hit open road again. There are times I set my ACC to 90 mph in a group when the speed limit is 80 mph in certain interstates out west.

ACC is still way better with its flaws compared to old fashion CC.

knakane

yep, agreed...it brakes way to hard for me..i only use it on open highway - for example, a couple weeks ago driving back to SoCal from Monterey, CA, on the boring, empty, straight 101S, I turned on ACC/CC + LCAS and pretty much kept one figner on the wheel and let the car drive itself. I only had to intervene a couple times when there were slow drivers to weave through.

Stew4HD

I don't like the way it brakes excessively when a car cuts in front of me in traffic so I don't use mine except out on the open highway.

BLEXV6

I have had it in my last RDX and new MDX. It is annoying when people cut in front of you on the highway and the cruise brakes for you and cars in front are driving slower and it slows you down. That said, when there is a lot of traffic, it's tough to use. I usually just use it when it is clear sailing.

likerage

I've had ACC in four different manufacturers so far and have found that Mercedes is the only so far that got it right. Audi, Chevy, and Acura/Honda need to hit the drawing board again.

RobinL

That’s what it’s supposed to do and why I like it. It tries to keep you at the distance from the car in front that you selected. If a car pulls in front of you, it’ll keep you a safe distance. Without adaptive, you would have to brake manually.

Stew4HD

I rarely have to brake when someone going roughly the same speed changes lanes in front of me, most often I just take my foot off of the pedal and coast to regain a safe gap. The ACC will hit the brakes pretty hard in the same circumstance.

I do know ACC is doing its best to keep a safe distance.

markm929

How does the Mercedes get it right?

likerage

A few ways.
First, when you are behind someone that is going below your designated speed and you turn on your turn signal to pass, the Merc immediately starts to accelerate rather than completely changing lanes and the car accepting that you are in a new lane before starting to accelerate. This may sound dangerous but its natural, I don't know anyone that completely changes lanes and counts to three before accelerating.
Second, if you are at full designated speed coming up to slower traffic that is starting to speed up, say a red light just turned green, the Merc would assess that the car in front is accelerating and the Merc would not slam on its brakes to keep you at the specific distance but would rather let off the gas and allow you to get closer than you otherwise would because the Merc is expecting the car in front to continue accelerating.
Third, when you are behind someone that is changing speed often, the Merc wont slow and speed up with any significant urgency, it matches what a normal human would do. The Acura constantly speeds and slows with unnecessary urgency. If I were a passenger in a car where someone was driving that way I would remark on it. Its a huge waste of gas.
Fourth, if you're in the right lane and someone passes you but pulls in your lane earlier than they probably should have, the Merc assesses that they are going quicker than you are and it wont let up or touch the brakes at all. It anticipates the car will be at a safe distance shortly.

Places the Merc fell short was lane keeping on long bends at highway speeds, it would bounce between the lines making you look like a drunk driver. Audi and Acura are better at lane assist.
All of my assessments are based on a 2016 Audi, 2017 merc, 2018 Chevy, and 2019 Acura.

DriverOne

I'm probably in the very very small minority of people, but I hardly use any of the technology that is in my Acura. I think I'm really old-fashioned. I use the backup camera, which is practically mandatory since you can't see out the rear, and I do rely on the blind spot indicators, since the vehicle is higher than a lot of sedans, but I still do turn to look. Other than that, I don't use much. I have the LKAS turned off because the first few days I drove, it would always alert and jerk my wheel when I changed lanes or merged lanes (I don't know if it's supposed to do that or not, but it did). Also, I'm of the belief that if you can't stay in your lane without assistance you shouldn't be driving at all. I don't drive far enough on highways regularly for cruise control, but I guess if I had to take a long road trip I would use it. So it's sort of weird seeing you guys debate it.

likerage

I use neither the LKAS nor the distronic cruise on the Acura because they don't work particularly well (as in work in a natural fashion) in city driving. I don't drive on the highway much so can't say much about that. I used them both on the Mercedes all the time because they were fantastic, especially in traffic.

Whats the point in buying something with all this tech if you aren't going to use it? You can spend far less money on cars without it.

DriverOne

Well, the thing that auto reviewers have raved about is that Acura made almost all of their safety systems standard across all trims, so I basically had no choice. If I could have opted out to save money, I would have. Same with the panoramic roof. I wasn't looking for that and I don't think I've opened it once. It's certainly nice for passengers, but it really doesn't affect the driver at all, but it's standard. I got the Advance because I wanted the SH-AWD and I thought the heated and ventilated seats would be nice and few other things that I forget by now, ha ha. It would be a perfectly good car without most of the tech, IMO.

DriverOne

I will say that I do rely heavily on the parking sensors. The body of the RDX is really tough to handle. I can't get a feel for where the front or corners are for some reason, so I can't tell when I'm going to hit something. I fortunately live in a semi-rural area, so I actually never have to park near anyone if I want to. So thus far, I have just parked away from other cars. But if I was in a place where I had to park in a small space with cars on either side of me, I would be pretty nervous. I'm coming from a sedan and never had any problems with that. Like I could whip it around anywhere and I had an excellent feel for where the car "ended." Is that just me?

markm929

Thank you for clarifying.

cincybill73

There are times that I prefer traditional cruise control. That mode can be selected by holding the cruise interval selection button for one second. See page 469 in the 2019 Owner's Manual.

MT-RDX

Yotrek said it best above - "That's how ACC works", if it isn't working well in your situation, turn it off. I find ACC to be the most useful technology on the RDX, but most of my driving is outside of urban areas (actually, ALL of Montana is outside of urban areas). I have rarely found any situation in city traffic where it is useful, except to keep me from running up too close the car ahead if I get careless.
One feature that is very useful in close traffic situations - ANY pressure on the gas pedal causes the ACC to drop its control, then you can drive normally (coasting down to restore the gap without letting the RDX brake hard , accelerate to pass without the surge from the ACC, follow a line of cars whose speed is varying, etc). When traffic permits and you're ready to return to ACC mode, take all pressure off the gas pedal, the ACC will resume control right where it left off. You can see the effect in the MID or HUD - when you touch the gas pedal, the set speed display goes blank and the ACC relinquishes control, when you let off the gas pedal, the set speed appears again in the display and the ACC resumes control.
One gripe for the ACURA programmers - when following a car that takes a freeway exit, the RDX frequently brakes hard even though the car ahead is well off the lane I'm travelling in. Causes an unnecessary hesitation, in heavy traffic can be quite irritating and totally unnecessary.

Madd Dog

I like how it works. In medium to heavy traffic, I put it on the shortest distance, and remain vigilant. Better than tapping it up and own all the time. Which was better than having to reset it all the time, which was better than not having any at all.

likerage

I have seen that same behavior in all the manufacturers I've driven.