As previously reported on this forum, my 2014 MDX Tech also makes a low frequency vibration whenever it passes through 1500 and 2000 RPM, at speeds between 25 to 50 MPH. It is usually a short "phizzet" sound of only a second or two, but has gone on for as much as five seconds. The is no apparent impact to performance but one wonders what is causing the sound, and what long term damage may be being done.

I have taken the automobile in twice to have the matter addressed but the dealers view is that it is an intermittent, difficult-to-replicate problem that they will fix when whatever it is breaks. The problem is difficult to reproduce in the crowded traffic around the Acura dealership, but it happens with regularity on longer, smooth roads. I also discussed reported problems regarding the Cylinder Management System (CMS) with the technical adviser and the mechanic and neither had even heard of the CMS, much less of a problem with it.

I have also reported the problem to Acura Customer Support but all they did was take a report and promise to contact me if a correction to the problem (aka recall) is released.

All-in-all, I sincerely wish I had not purchased this automobile simply because of its (1) poor rearward visibility and nerve-racking collision avoidance system, (2) attention diverting interfaces (just finding a radio station is a challenge) and (3) rough ride. The incessantly annoying vibration is simply the final straw.

At this writing I have owned the car for a year and have 10,000 miles on it. I will not keep it another year.

Update from Mar 25, 2015: Okay, the fix for this problem is contained in Acura Service Bulletin 14-003, dated Feb 4. 2014. The Symptom reads: There is a grinding, rattling, vibrating, fluttering or buzzing noise coming from the front of the vehicle under light acceleration with engine speed under 2,000 rpm.

The Problem is that: "The bulkhead cover fasteners (latches and strikers) have become detached".

The Corrective Action is to: "Replace the bulkhead cover latches and strikers."

Takes about 30 minutes to fix. Had mine replaced on 3/23/2015 AND IT WORKS.

It is such a relief not to hear that strange buzzing vibration. Why Acura has not notified all 2014 MDX owners of this fix is beyond me.

This very noticeable noise, which sounds like very short (1 second vibrations and as long as 5 second vibrations), occurs while driving at speeds from 20 mph to 50 mph but more often at the high end. It comes from under the hood directly in front of the driver's seat. An Acura dealership informed me I wasn't the only one with this complaint and that it has something to do with the 'cylinder management system' which is new to the 2014 MDX model year (re the new 3.5 engine). Apparently Honda cars with the available CMS have had this problem for the past few years. No fix was forthcoming from the dealership rep and he told me the regional Acura rep was keeping them apprised of the situation.

I have owned a new 2009 RDX, a new 2011 MDX and now this one and I will say that if Acura/Honda doesn't own up to this problem and fix it I will switch allegiance and likely move to Lexus next time.

Please see 'other' problems I'm having with this car.