2013 SEL - Loud noise while accelerating

[SillyBear]

Hi all,

 

I've been a lurker for a few months now, bought my 2013 C-MAX in January, and I've been loving everything about it. It performed admirably during a rather harsh winter in Canada and now that summer is coming I can't wait to take it on extended drives.

 

Now for my main reason of posting. For about 3 months now I've been noticing a rather loud humming noise when I'm accelerating and the ICE is on. This predominantly only happens when I'm on a bit of an uphill and the RPMs are between 2300 to 2500. If I left off the gas, the loud hum stops and it sounds like a normal car accelerating, or if I press a bit harder and exceed 2500 RPM the noise also disappears.

 

The noise inside the cabin makes my C-MAX sound like I have one of those large fart cannon exhausts on my vehicle and believe I cringe when those ricers drive by.

 

I took it to Ford and even took a technician out with me and he claimed that it's normal for the car to make this noise if it's under a specific load. I explained to him that it wasn't like this when I first got it and it's something that developed, but he kept reassuring me there's nothing wrong with it, even went as far as telling me that I'm now "listening" to the car more since the new car high has passed.

 

So here I am, still questioning whether there's something wrong with my C-MAX or not. I'm hoping someone might be able to help shed some light on this issue, whether the tech is right or if I should go seek another opinion.

 

Also quick side note, does anyone else's pano roof curtain work only half the time? My daughters ask me to close it sometimes and it doesn't work. I have to put the car in park, shut it off and on to get it working again. Quite odd.

 

Thanks in advance!

[mlsstl]

You could ask the dealer for a test ride in another C-Max off the lot and see if it is making the same noise under the same conditions. That should go a long way toward settling the question of whether yours is acting "normally".

[Bill-N]

You could ask the dealer for a test ride in another C-Max off the lot and see if it is making the same noise under the same conditions. That should go a long way toward settling the question of whether yours is acting "normally".

 

I agree.  After taking delivery of my SEL, I was concerned about a diesel-like sound when the engine was under light load.  Tried another C-Max at the dealer and it made the exact same sound so now I know what's normal.

[markd]

I think that it's because the car is typically very quiet. I hear it too.

[SillyBear]

I think that it's because the car is typically very quiet. I hear it too.

That's what I thought too, but this seems abnormally loud. Always in the specific RPM range. I had my windows down today and it was very noticeable.

[markd]

I hear it too, my car has 7500 miles on it and I 'be been thinking about taking it in. I notice it mainly when I'm accelerating from a stop up until I let up on the pedal, and it doesn't do it all of the time.

[SillyBear]

I hear it too, my car has 7500 miles on it and I 'be been thinking about taking it in. I notice it mainly when I'm accelerating from a stop up until I let up on the pedal, and it doesn't do it all of the time.

If you have time, can you identify at what RPM it occurs? Mine is always in the 2300 to 2500 range.

[wab]

Take a look at this thread.

WARNING: This is a very long thread and several people lose all self-control.

 

We hear the wooo below 45mph going up hill BUT ONLY when it's cold (anything below 30*F is considered cold in N Texas).

 

Start on post #15.

http://fordcmaxhybridforum.com/topic/3457-strange-long-wooooo-sound-at-steady-speeds-ice-on/

[raadsel]

Take a look at this thread.

WARNING: This is a very long thread and several people lose all self-control.

 

We hear the wooo below 45mph going up hill BUT ONLY when it's cold (anything below 30*F is considered cold in N Texas).

 

Start on post #15.

http://fordcmaxhybridforum.com/topic/3457-strange-long-wooooo-sound-at-steady-speeds-ice-on/

 

Anything below about 60F is considered cold in the coastal part of Texas.   ;)

Edited May 5, 2015 by raadsel

[SillyBear]

Take a look at this thread.

WARNING: This is a very long thread and several people lose all self-control.

 

We hear the wooo below 45mph going up hill BUT ONLY when it's cold (anything below 30*F is considered cold in N Texas).

 

Start on post #15.

http://fordcmaxhybridforum.com/topic/3457-strange-long-wooooo-sound-at-steady-speeds-ice-on/

Thanks for pointing this out. My car has the exact same symptoms. After reading the entire thread and sifting through the bickering, I'm going to present my findings to my dealer and request they start with the referenced TSB. I'm also going to unplug fuse 22 and see if that changes anything.

 

I love my cmax and if I can get that noise to be half as loud then I'll be quite content.

Edited May 6, 2015 by SillyBear

[FordService]

I hear it too, my car has 7500 miles on it and I 'be been thinking about taking it in. I notice it mainly when I'm accelerating from a stop up until I let up on the pedal, and it doesn't do it all of the time.

Hi markd,

 

I'll be happy to check out some additional assistance to see how we can hush the humming. Please PM me your VIN, best daytime phone number, full name, and dealer name/location. I'll get right on it. :)

 

Meagan

[markd]

Meagan, since it only does it randomly I'm going to wait, but thank you very much.

[FordService]

Meagan, since it only does it randomly I'm going to wait, but thank you very much.

No worries. Feel free to reach out if you do end up going. :)

 

Meagan

[SillyBear]

No worries. Feel free to reach out if you do end up going. :)

 

Meagan

Is there a similar Ford rep on here who deals with Canadian owners?

[FordService]

Is there a similar Ford rep on here who deals with Canadian owners?

Sure is!  I've reached out to FordServiceCA to take a look, but you can also PM them directly. :)

 

Meagan

[FordServiceCA]

Hi all,

 

I've been a lurker for a few months now, bought my 2013 C-MAX in January, and I've been loving everything about it. It performed admirably during a rather harsh winter in Canada and now that summer is coming I can't wait to take it on extended drives.

 

Now for my main reason of posting. For about 3 months now I've been noticing a rather loud humming noise when I'm accelerating and the ICE is on. This predominantly only happens when I'm on a bit of an uphill and the RPMs are between 2300 to 2500. If I left off the gas, the loud hum stops and it sounds like a normal car accelerating, or if I press a bit harder and exceed 2500 RPM the noise also disappears.

 

The noise inside the cabin makes my C-MAX sound like I have one of those large fart cannon exhausts on my vehicle and believe I cringe when those ricers drive by.

 

I took it to Ford and even took a technician out with me and he claimed that it's normal for the car to make this noise if it's under a specific load. I explained to him that it wasn't like this when I first got it and it's something that developed, but he kept reassuring me there's nothing wrong with it, even went as far as telling me that I'm now "listening" to the car more since the new car high has passed.

 

So here I am, still questioning whether there's something wrong with my C-MAX or not. I'm hoping someone might be able to help shed some light on this issue, whether the tech is right or if I should go seek another opinion.

 

Also quick side note, does anyone else's pano roof curtain work only half the time? My daughters ask me to close it sometimes and it doesn't work. I have to put the car in park, shut it off and on to get it working again. Quite odd.

 

Thanks in advance!

 

Hey SillyBear, 

 

Have you considered seeking a second opinion at another dealer? Locate dealerships in your area here. Also, let me know the current odometer reading and I'll see how to best assist on my end. 

 

 

Sure is!  I've reached out to FordServiceCA to take a look, but you can also PM them directly. :)

 

Meagan

 

That would be me! Thanks, Meagan!  :thumbsup:

 

Mariel 

[John Sparks]

I know this sound that the engine is making. It's a harmonic vibration that occurs when certain load conditions occur. It's completely normal. I have 46,000 on mine and it has been doing it since day one. I generally only notice it when my family is in the car. This being because I'm using my normal driving techniques with more weight in the vehicle. It's loud and a bit annoying but "generally" only occurs under light acceleration or load. As you have said yourself, apply more gas or let off and it goes away. This is nothing to be concerned with.

 

I have also experienced the "whoo" sound but have never chimed in on it. I generally only hear it when riding with my windows down. I do not believe this is anything to worry about either. It's just the sound of the electric motor transitioning back over to the ICE. My belief is that in some conditions to avoid an abrupt start of the the engine, it more or less eases into it resulting the long whoo others have describe on the the other thread mentioned above.

[djc]

Mea culpa, I started another thread on this.  Judging from the posts, it is normal, but perhaps is temperature related.  Mine has gone away since temps have risen above 70.  It was serious when temps were in the 30s.   Is a temp effect noticed by others?  Do cars used in places with eternal sunshine not experience the noise?    If there is a temp effect, then maybe thermal contraction or stiffening of an engine mount is the ultimate cause of the problem.

[Jenie Benson]

Mea culpa, I started another thread on this.  Judging from the posts, it is normal, but perhaps is temperature related.  Mine has gone away since temps have risen above 70.  It was serious when temps were in the 30s.   Is a temp effect noticed by others?  Do cars used in places with eternal sunshine not experience the noise?    If there is a temp effect, then maybe thermal contraction or stiffening of an engine mount is the ultimate cause of the problem.

What you probably read if you read the other thread all the way through is that my dealership and I have come to the conclusion that the source of the noise is vibration in the drivetrain somewhere, but that it is being transmitted through the car and amplified by the ANC.  That is why when pulling fuse 22 in my car and listening carefully, I could still hear the frequency, but it was quiet enough that had it always been there at that level, I never would have noticed it. The RPM range is right in that 2300-2500 range and for my car it has to be under 35 degrees outside (so it doesn't present itself in the warmer months).  My dealership tried replacing a motor mount that they thought was the culprit.  They used one that is actually for a Focus which was from a TSB for a similar issue a few years back.  However, that did not solve the issue.  Currently, Ford has ZERO idea what is causing this exactly or how to fix it and keeps directing my dealership to fiddle with the ANC to try to get the noise to stop. However, all attempts to do that resulted in a hands free system that can no longer understand me when the ICE is engaged because it's trying to cancel too much noise. I don't have the panoramic sunroof, so I doubt that's an issue. Mine is an Energi, but I have chatted with others who have the non-Energi and have the same issue. So far, Ford is declining to admit there is really a problem even though there are a number of us with this same issue. I asked to initiate buy-back and was told Ford wouldn't buy my car back by a regional Ford rep, so I'll be forced to sue under the state's Lemon Law to make it happen. Sad too, cause this was really the car I wanted, and I love it except for the totally unfixable issue which has made driving it on the interstate at cruising speed in the winter unbearable (it vibrates through the wheel and seats and makes my hands hurt and my body tired if I have to drive more than just around town). And I love the MPG, but not enough to put up with the problem anymore.

[djc]

Thanks Jenie.  I am sorry to hear about your experience!

I have now read the other long thread on the noise.  It is very interesting that pulling fuse 22 helps the problem. 

 

A 2012 Ford press release touting the noise cancellation system says:

"At the lower speeds that help efficiency, engines produce booming, low-frequency sounds that can be unpleasant to the driver and passengers. Without Active Noise Cancellation, engineers have to keep the engine out of this operating range, sacrificing efficiency."

So Ford introduced ANC with its 2013 hybrids so that they can operate their engines at lowish rpm with heavy load.

 

So currently I am thinking:

The noise problem has at least two components: the noise source, and the ANC.  Ford seems to be saying, in the press release, that the source is the engine.  That squares with others reporting that the noise occurs only when the engine is on, and is specific to a narrow rpm range. 

Another factor may be whatever transmits the vibration or resonates to the vibration.  As you and I and others have noticed, the noise is worse in cold temps.  Cold temps may affect engine mounts, or the body panels near them.  It is not obvious to me how temp could affect the ANC.  I believe there are 2 main engine mounts (the driver side one is on the transmission), and a third connection or damper in the middle.  The two main mounts connect to the main frame members at the side of the vehicle.  The third connection may be to the firewall.  Hmm.   I will try to look when the car is up.

 

The ANC may work well most of the time, but may be baffled by specific frequencies.  It may also misbehave when windows are open (or partially open) at high speeds, worsening a buffeting noise.  Also yesterday driving on a seriously washboard gravel road there seemed to be much more noise in my C-max cabin than could be explained just by the tires on the ruts.

 

So I would like to be able to disable the ANC.  I would therefore like to know where the module is.

Meanwhile it seems relatively straightforward  to replace fuse 22 with a remote switch.  That would allow switching the ANC on and off during the noise and noting the effect.  A switch might also provide a partial remedy when the noise is really disturbing.
 

 

[jdbob]

The ANC is done within the Digital Audio Control Module. But since it's the one that drives all the speakers (except the center console speaker - if equipped) pulling F22 turns off your stereo as well.

 

I would think that the only way to get rid of ANC would be to short out each of the 3 microphones. Probably a nightmare to find the right cable.

[djc]

Yes, an alternative would be to shut down some / all the mics.  They must go to a connector somewhere.

Where is digital audio control module?  If it is in dash area, as one would expect, it is odd that its fuse is in rear compartment along with fuses for rear stuff? 

 

In any case I was thinking of putting  a normally closed pushbutton switch at the console.  Pressing the button would open the circuit through F22.  Pressing the button when the car is making droning / booming noises would clarify how the ANC is / is not contributing to the problem.  I don't normally listen to radio / audio so will not lose anything, assuming it doesn't do more than shut off sound system.

Also I am wondering if the noise problem varies at all with car occupancy - in particular whether someone is in the passenger seat.  Occupants will modify cabin acoustics and what the mics pick up, and hence may affect how ANC behaves. 

Meanwhile I will try to track down name of Ford noise control engineer...

[djc]

Update:

In the workshop manual the Digital Audio module is shown behind lower far left of dashboard, near where the obd-ii socket is.

I disabled ANC yesterday by pulling fuse F22 in the cargo area and noticed no noise in a variety of engine load conditions that produced loud noise in colder weather.  Looks like there is room in the fuse row to allow replacing the fuse by a fuse modified to become a plug for a remote on/off switch.

 

Related: there is a thread on the Ford Fusion Hybrid forum about a change in the design of the air intake pipe.  The change is a resonator on the side designed to control engine noise.  It seems all Lincoln MKZ hybrids have this resonator on the intake, and Fusion hybrids added it in 2013 before 2014 model year production.  Some who replaced the original with the resonator intake believe it has reduced noise; some recent posts did not notice an improvement.

 

http://fordfusionhybridforum.com/topic/8292-air-intake-wresonator-installation/

[iammikeo]

I know exactly what you're saying. Not sure if my videoclip really captured how loud and irritating the noise is but..

 

http://youtu.be/dUDLpAeyhjM

[banex25]

A

Edited March 10, 2020 by banex25