[ole]

Does anyone else notice a buzzy vibration when the ICE is used while accelerating slowly? I can hear it and also feel it, most noticeable through the steering wheel. It is especially noticeable between 35 and 50 MPH. When acceleration stops and I hold speed constant the buzz will continue for 5-10 seconds and then it feels like it is finally engaging something (like slipping into gear) and the vibration stops until I accelerate again. It doesn't seem to be the ICE itself because it keeps vibrating for several seconds after the RPM drops. If I go above the speed I want while accelerating by just slightly and then let the speed drop down the vibration stops immediately and I feel the same "something engaging" feeling (no delay).
This started after just a few uses of the ICE. I hardly ever use it. Mostly flat roads with max 50 MPH speed limit, usually 45. SW Florida warm temps.
I took it to the dealer and they didn't even try to fix it because I had too much battery range left so they couldn't get the ICE to run! They apparently had never heard of Hold mode! I can recreate it every time in Hold mode but they weren't interested in having me show the tech.

2017 Volt Premier
Build Date 11/16
12,000 miles

 

[VoltenRock]

How many miles do you have on the gas engine? I have a 2017 with a close build date (12/16) and have all kinds of NVH in ICE mode--and it seems especially worse 35-50 MPH. I've got about 600 miles on the ICE.

Some have said that these issues get better with a little more gas miles, but gas miles can be hard to get in a Gen 2!

 

[Arcanox]

My ICE vibrates a lot when it's revved up, and it stays revved up for several seconds even after I level out my acceleration, which is obviously different from a normal car. Could it be that this is what you're noticing? The ICE will stay revved up to recover some of the energy it used from the battery to bring it back up to its set point. Then, once it "catches up," it drops the RPM and clutches the engine into the transmission (between about 40 to 55 MPH) and it becomes mechanically connected to the wheels until you begin to accelerate heavily again. This matches what you describe. The "slipping into gear" is quite literally what is happening; it tries to get the engine to an RPM that matches the wheels, then clutches it in, so you feel it engaging similar to a gear shift in a normal vehicle.

 

[TheBlueFlash]

Both the ICE's in my 2013 and 2016 are incredibly smooth. There are some service campaigns out for the gen 2 that addresses some ICE issues. I would go to the dealer and make sure your software is up to date. NVH could be caused by misfires which is specifically addressed by one or more of those campaign updates.