Quieter engine after oil change

[Madevilz]

About a month ago, my wife told me my engine sounded louder when accelerating. I kinda noticed the same. My oil change wasnt due before another 5k+ miles, and the oil color/level all looked good. Went to the dealer yesterday, and did my oil change sooner than the recommended interval. I immediately hear a difference upon driving, the engine did sound quieter. This was my first oil change as I bought it 6 months ago. Dont think it is my imagination, does older oil make the engine louder?

Asking so I stop worrying about any engine damage done when it was louder lol

Ford Fusion Energi 2017

Edited February 29, 2020 at 02:14 AM by Madevilz

[jj2me]

There are so many variables with our cars having Active Noise Cancellation (at least it's listed as standard on my 2017 Titanium).

 

You say you were driving, and your wife heard it when accelerating, so both times it was in-car sound, subject to the ANC algorithm.  Windows down?  Windy outside?  Road surface different?  Radio on?  Talking?  More people or objects in the car absorbing sound such that the microphones pick up less noise?  Accelerating harder and thus producing some noise above the ANC's working range?  Etc.  Maybe even the oil-change person saw something loose underneath the car and tightened it, changing the register you'd hear.  Really tough to diagnose in hindsight (unless someone else here chimes in with a possible oil-related reason for the differences you've heard).

[Madevilz]

50 minutes ago, jj2me said:

There are so many variables with our cars having Active Noise Cancellation (at least it's listed as standard on my 2017 Titanium).

 

You say you were driving, and your wife heard it when accelerating, so both times it was in-car sound, subject to the ANC algorithm.  Windows down?  Windy outside?  Road surface different?  Radio on?  Talking?  More people or objects in the car absorbing sound such that the microphones pick up less noise?  Accelerating harder and thus producing some noise above the ANC's working range?  Etc.  Maybe even the oil-change person saw something loose underneath the car and tightened it, changing the register you'd hear.  Really tough to diagnose in hindsight (unless someone else here chimes in with a possible oil-related reason for the differences you've heard).

 

Windows all up, with heater on, pretty cold over here :)

Normal driving condition. Sound is just like normal acceleration, but louder, not like a tank, but I mean, slightly louder that makes it noticeable to someone driving it every day. And even to my wife who only gets in once a week or so.

 

Maybe it could indeed be something loose. Had a 30pt inspection included with the oil change, maybe they unscrewed some stuff out and put them back, tightening them at the same time. I mean, if it had anything with the oil, they would have mentioned it right? Inspection came back all good. 

[murphy]

It has an Atkinson cycle engine instead of the "normal" Otto cycle.  They are normally louder.  There is a sound resonator in the air intake path to reduce the noise level caused by the intake valves opening before the end of the combustion cycle.  Any chance the previous owner modified the sound system?  That would detune the active noise cancellation system.

 

[Madevilz]

54 minutes ago, murphy said:

It has an Atkinson cycle engine instead of the "normal" Otto cycle.  They are normally louder.  There is a sound resonator in the air intake path to reduce the noise level caused by the intake valves opening before the end of the combustion cycle.  Any chance the previous owner modified the sound system?  That would detune the active noise cancellation system.

 

No mods. We only noticed acceleration being louder a couple of months ago or so. After the oil change a few days ago, it sounds normal, like when I bought it.