[Smiller461]

Does anyone notice a weird knocking sound coming from under the front driver side floor board when accelerating and or breaking? It doesn’t happen all the time but will randomly do it at times. I am not sure what it is, nor what causes it. Any insight into this problem?

 

[insightfully]

My EX runs pretty quiet/silent, without any knocking noise. I've often driven the car without the radio on, to get a feel for what the car 'normally' sounds like. There is a slight 'whirring' sound I hear from the electrical components, but not much else.

Some questions: How loud are the sounds you hear (e.g. faint vs obvious/noticeable)? Do you feel any vibrations when the sound occurs? Does it happen when both the gas engine and electric motor run, or just when one or the other runs? Does the sound happen when the car is cold, or after it has warmed up?

 

[Mr. Natural]

Have you taken a look under the car? My wife mentioned a noise from her car once (not the insight) and there was a small branch hung up under it.

 

[hasarad]

My wife has a knack for running over plastic bags and getting them stuck under her car. There is nothing under the floorboard that should knock unless something external got stuck there. Is the sound timing going along with wheel rotation?

 

[Mobilcams]

I noticed during the first 3000 miles the brakes made some noise when I hit the brakes in reverse at times. It was a definite knocking noise. Since then it doesn’t make that noise anymore.

 

[Smiller461]

I personally think they are noticeable and well more felt than heard. Idk how to explain it but the best way I can is it feels like something is rolling under my seat and hitting the back of my foot. Obviously I’ve checked and there is nothing loose under my seat that would roll and I looked under the car and didn’t notice anything caught up.
I am not sure exactly which one I am in when it happens, I believe it’s the gas engine side more than the electric side. And it mostly happens when the engine is warm. It usually doesn’t happen when I first start driving but after a bit it will.

My EX runs pretty quiet/silent, without any knocking noise. I've often driven the car without the radio on, to get a feel for what the car 'normally' sounds like. There is a slight 'whirring' sound I hear from the electrical components, but not much else.

Some questions: How loud are the sounds you hear (e.g. faint vs obvious/noticeable)? Do you feel any vibrations when the sound occurs? Does it happen when both the gas engine and electric motor run, or just when one or the other runs? Does the sound happen when the car is cold, or after it has warmed up?

 

[insightfully]

I personally think they are noticeable and well more felt than heard. Idk how to explain it but the best way I can is it feels like something is rolling under my seat and hitting the back of my foot. Obviously I’ve checked and there is nothing loose under my seat that would roll and I looked under the car and didn’t notice anything caught up.

I am not sure exactly which one I am in when it happens, I believe it’s the gas engine side more than the electric side. And it mostly happens when the engine is warm. It usually doesn’t happen when I first start driving but after a bit it will.

On older cars, I'd think what you're describing could be worn CV joint/shaft, steering issue, suspension issue, or exhaust system heat shield (or maybe even a motor mount/bearing?). BUT it's hard to make the leap that your brand new car would have these issues already. You're covered by Honda's new car warranty and I think you should bring it in if you don't find obvious physical issues that were already suggested. However, you'd get better assistance and resolution from Honda if you can narrow down the type of issue and conditions under which they occur.

Since the issue as intermittent, it might help Honda diagnose if you can video the issue and/or document conditions when it occurs. If personal video doesn't work, suspension and alignment mechanics can use a set of microphones connected to headphones, where the microphones can be moved to suspect points and driven around while listening to zero in on the source of the noise. Or perhaps your Honda dealer would have something like this.

It might also help the troubleshooting to narrow down the engine condition under which the issue occurs. To determine whether you're in hybrid, electric, or gas (direct drive) mode, try having the "Power Flow Monitor" up on the infotainment OR on the drivers info interface. (It's available to view in both places.) Alternately, try some less-precise indirect estimators:
- if you see the green "EV" indicator in the lower left corner when the noise occurs, you're in electric mode
- if you see the dial on the left 'power/charge' circular indicator running in the 'gray' areas, you're in gas (direct drive) mode
- if you don't see the "EV" indicator and are running in the blue or green part of the 'power/charge' indicator, you're likely in hybrid mode (though it could also be in this condition for gas-only mode... thus the cross-reference suggestion to power flow monitor)

 

[Mobilcams]

I know what you're talking about!! It's nothing to worry about. Sometimes when the engine comes online - there may be a little kick back while starting.. It is at times noticeable, but nothing to worry about at all.. You will notice it as well when you are in park and the car has rolled into the locked position and you are idling.. When the engine comes on in this configuration - it will shake the whole car slightly. I really wouldn't worry too much about it.

 

[Min Pin]

Yes, I hear it.

Does anyone notice a weird knocking sound coming from under the front driver side floor board when accelerating and or breaking? It doesn’t happen all the time but will randomly do it at times. I am not sure what it is, nor what causes it. Any insight into this problem?

Yes, I heard it couple of times in the past, but now I can repeat the sound everytime.
Move back or forward 6 inches or so and step on the brake just enough so that car rocks.
The video sound is from outside so it sounds more metallic, but from the inside of the car, it's more of hollow knocking sound. I have no idea where the sound is coming from and I feel I don't need to (or should not) do this too many times.

 

[hasarad]

Yes, I heard it couple of times in the past, but now I can repeat the sound everytime.
Move back or forward 6 inches or so and step on the brake just enough so that car rocks.
The video sound is from outside so it sounds more metallic, but from the inside of the car, it's more of hollow knocking sound. I have no idea where the sound is coming from and I feel I don't need to (or should not) do this too many times.

https://youtu.be/TbP_u5qC6G0

Vid comes up as unavailable. Permissions?

 

[Min Pin]

Thanks, I need to learn more about posting a video.

 

[Min Pin]

Video for the previous post.

 

[andrew28]

My Insight does that hollow knocking sound if I press on the brakes hard enough to rock the car. I learned to not press the brakes as hard when I come to a stop.

 

[andrew28]

My Insight does that hollow knocking sound if I press on the brakes hard enough to rock the car. I learned to not press the brakes as hard when I come to a stop.

I need to correct myself. I went to move my car just now and when I hard brake it makes a creaking or squeaky sound instead of a hollow knocking sound.

 

[hasarad]

That knock is not normal. It almost sounds like there is a brake pad that is loose in the caliper when you stop and the car rebounds. Let the dealer take a look.

 

[dvom]

Knock when accelerating from a stop

I have a single knock/clunk from in front of the driver area when starting out from a stop accelerating normally. It will not make the noise if I accelerate slowly. It is not tied to the engine turning on and can be felt and heard through the floor/brake pedal area. Brakes never make noise it is only accelerating. The car has 5k miles and is an ex.

 

[insightfully]

I have a single knock/clunk from in front of the driver area when starting out from a stop accelerating normally. It will not make the noise if I accelerate slowly. It is not tied to the engine turning on and can be felt and heard through the floor/brake pedal area. Brakes never make noise it is only accelerating. The car has 5k miles and is an ex.

Welcome to the forum. Added your question to this thread, as it sounds like it might be related. Is the sound similar to the video posted above by @MinPin? If not, can you share video example of what you observe?

 

[hasarad]

I have a single knock/clunk from in front of the driver area when starting out from a stop accelerating normally. It will not make the noise if I accelerate slowly. It is not tied to the engine turning on and can be felt and heard through the floor/brake pedal area. Brakes never make noise it is only accelerating. The car has 5k miles and is an ex.

Do you use brake hold?

 

[dvom]

Do you use brake hold?

I just found this thread today. No I do not use brake hold and do not set the ebrake when parking. It is a similar sound as the video but I'm sure it is from the front. First thing on my list to try is to tweak the front brake pad fit kit a little tighter and add small amount of grease to the corners of the front pads and recheck it, the front pads may be moving too much. But if I had to guess its something more involved, its a pretty substantial clunk.

 

[andrew28]

FWIW, the Honda tech that worked on my car to fix the brake creaking sound told me what @Min Pin 's video shows the rear wheels doing is normal including that sound. My Insight still does that sound in the rear wheels even though the brake creak/groaning sound is gone.