sometime here alot of noise on running on gas engine, also MPG average dropped from 45 to 40.1 insteadly after happening this issue

[anthony sushi]

before i dont have problem when press on gas paddle , run so smooth and accelerate so fast no hear any sound ,  (i believe it run on electric )

now when i press on ga paddle , make a lot of sound , ev mode switch to engine mode,  gas MPG dropped to 45 to 40.1  

car still running ok, but make alot of sound on engine mode, when it back to electric mode no sound, when back to engie mode hear loud noise.,

Did anyone have this kind of problem? really appreciate any info

 

 

[homestead]

It's normal for there to be more noise when the engine turns on vs running on the battery only.

You can post a recording here of the noise if you think it's a problem.

[Adrian_L]

My hybrid has 180,000 km (112,000 miles) and over the last month, I have noticed a significant increase in noise from the engine compartment (typically while driving over 50 mph).    I'm going to investigate (maybe wheel bearings?) but would be curious if owners of higher mileage C-maxes have noticed a change.   

[grege]

Wheel bearing is quite possible.  If you can load some audio of it, that'll help diagnostics.

Greg  

[Chuckee]

On 5/26/2024 at 7:30 PM, grege said:

Wheel bearing is quite possible.  If you can load some audio of it, that'll help diagnostics.

Greg  

My increase noise level of engine and of road happened suddenly.  I'm sure it's the Adaptive Noise Cancellation (ANC) but the dealer says it's "normal".  I have the Energi and the service manager likely tested it in electric mode where it is quieter engine wise but not road noise.  With the Energi, the car runs of plug-in battery until that is depleted then switches to hybrid mode so likely the service manager did his road test in electric not realizing it was in electric.  My car is 8 years old and the C-max is not made anymore so I wonder if the service manager is familiar with how ANC works.  ANC is an electronic module that samples the interior car noise and tries to cancel it out.  I think the speakers is in the back and that is where the road noise comes from.   Only have 18K miles so not likely any other problem, and like I said on the same day it changed for quiet to noisy between shutting the engine off and turning it back on after some shopping.  Would appreciate any comments by a knowledgeable technician on my issue and how to convince the service manager of the problem.

[homestead]

You can disconnect the ANC connector and see what that does.  I believe it is under the dash on the passenger side.

[Chuckee]

47 minutes ago, homestead said:

You can disconnect the ANC connector and see what that does.  I believe it is under the dash on the passenger side.

I've discovered the ANC works first thing in the morning when the cabin is cool but fails in the afternoon if the sun is out and the windows are up.  I'm trying to get the dealer to go ahead and replace the ANC module and if not, I'm trying to get the module to fail for good by placing the car in the sun for long periods.

[Chuckee]

The 2017 C-Max Energi has been a fantastic car.  I've found that by running on the plug-in battery to point A and come back from point A in hybrid mode, I double the range of the plug-in battery and double the mpg of hybrid mode.  So I get 50 miles off the battery and 70 mpg----a win-win situation.  Also because the plug-in battery charges off of 220 V at 16 amps, I can piggy-back off my dryer circuit to charge the battery.  So no expensive 50 amp circuit as is required by electric only cars.