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The same with my 14 (also CPO and got the "AcuraCare" until 100K / 10 yrs which was a great idea since we got our money's worth so far). As for my issue, the software update definitely "fixed" the issue but do not know exactly what that update did (e.g., VCM update - I didn't even know I had VCM :) or just artificially increase the RPM / power output). After the software update, the shuddering / pulsing is gone at least when I drive (since this is my wife's I only drive this MDX once a week for 20-50 miles) and when I did tranny fluid flush (4 qrt x 3 times over a 2 week period), the rider is really, noticeably smooth and not a sign of pulsing. (oh, and also transfer case / real diff fluids, too, but this shouldn't impact the ride quality significantly).
 

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Is this happening only when the engine is cold or all the time?

There was a recall on the transmission to have the software reflashed and in the process drain and refill the trans fluid, which took care of that pulsating in my car; by the way mine was occurring all the time; they did say when the reflashed/drain and refill it that in some cases that pulsating returns which means they would have to redo that over again, but so far that hasn't happened. I'm leaning towards this since it seems to be an issue with Acuras. On a related note some Acuras had bad torque converters which for some reason were never recalled.
Note the RPM gauge, if your gauge is doing that then this could very well be your issue.

If it's not the above check your tires! You could have a problem with a tire, if you just got new tires they may have incorrectly torqued your wheels, anyway this is a cheap thing to check, simply take the car down to where you bought the tires and have them checked to make sure a tire isn't developing an issue. But I doubt this because you said it only occurs while accelerating, but it's worth a look.

A cheap thing you can do as a check is to switch off your VSA and see if that clears up the issue, if so then a brake sensor could be the culprit. If not the issue when you test that you could have a stuck brake caliper.

The other thing if its happening all the time and if the reflash doesn't take care of it is to clean the throttle body with throttle body cleaner spray, and change the PVC valve.

I could also be an O2 sensor fouling up or the EGR valve going haywire.

If it only happens when the engine is cold then the ECU needs be looked at because it may be leaning out the engine too much when cold.

Another issue is the drive transaxle could be bent or the CV joint is worn or damaged; as well as an alignment issue or a wheel bearing problem. Watch this video:
A professional can usually do these checks for free...in hopes of course to find something so they can charge you for a repair.

If the car has a lot miles on it you could have worn out or loose engine mounts; or perhaps loose vacuum line, or perhaps your plugs, wires, and coil pack are messing up.

You could have a damaged or worn engine, if one cylinder has lower compression than the others this would cause an imbalance in the engine, the only way to check that is to have a compression check, at the same time they do this request a vacuum check to make sure the valves are working and adjusted correctly because misadjusted valves (especially if just one cylinder is misadjusted) could cause your problem. Acuras by the way, about every 100,000 to 150,000 miles needs their valves adjusted, so don't dismiss this recommendation.

Lots of potential issues that can cause your situation as you tell, but you need to take care of all the cheap stuff first and slowly move into more and more expensive stuff.

The problem with today's mechanics is they are no longer trained on how to diagnose a car on their own, instead they rely on their computers instead, and if the computer says there are no problems then the mechanics sit around scratching their heads dumbfounded, so then they start replacing parts needlessly and charging you for it only to find out after you spent a small fortune in replaced parts that it was some other issue.

Honda and Acura had been having a lot of problems lately, it's sad too because they use to make such great cars but not anymore. I've have bought my last Acura/Honda car because of all the issues I've seen on the internet with their cars. Unfortunately Acura/Honda is not alone in these problems, in fact the ONLY car manufacturer that has most of their models rated above average now is just Toyota/Lexus, so when it comes time to replace my car that's where I'm headed; my truck needs to be replaced and I'm looking at the Tundra because they're stone cold reliable vs everyone else.
 

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I have the pulsing on my 2011 MDX under light loads only on slight uphills. It’s a cyclical pulsing where the RPMs bump up and down a couple hundred RPMs (with corresponding acceleration and deceleration). You can feel it pulsing at about 1 Hz. I usually push down a bit harder on the accelerator and it goes away.
 

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Discussion Starter #24
Wow lots of recent post and good discussion. I dropped off our MDX yesterday and picked it up today. They did the TSB Trans flush (3x drain and fill)?? Whatever - but that seems to have taken care of the pulsing. I like the video clips. I wish I would've got some of our issue. It pulsed as it climbed up in rpms. Sometimes it was obvious other times barely detectable. I still feel the TC slips more than it should but that's how its been since we got it (CPO 2 yrs old) July 2016. We do tow a 3000lb (empty) trailmanor trailer occasionally with the MDX (My Tacoma tows it so much better but its a truck -no surprize there I guess) and the TC slippage is not comforting so I use S mode and shift with the paddles when towing. I did install the factory tow pkg with cooler. As far as VCM I cant really tell when it doing its thing except maybe cruising on the HWY in 6th gear and then pushing the throttle and feeling a slight delay but even then barely noticeable. We usually have it in sport mode but I had it in normal recently because it seemed to be a little worse in that mode. For now its back to driving as it should it seems. Thank You to everyone who posted on this.
 

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I have a 15 MDX AWD Tech with 48k miles. I have noticed the same symptoms as described in this thread since about last 3 months with tech meter pulsating at low revs ang goes away when accelerating. I will be taking to dealer for possible trans software update (if available) and drain & fill of tranny fluid as I have not done that yet.
 

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18 months ago, I had the software update and fluid flush, which did satisfactorily address the pulsing.

Just noticed the same transmission pulsing again today. Ugh.
 

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Trans pulsing came back in our 2015 about 22k miles after TSB work. They redid the fluid exchange and it was back to normal. I expect this short fluid change interval will become routine service once we pass 80k miles.
 
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