Acceleration Buzzing Sound (CT4-V Blackwing)

[Seth]

Okay. I first noticed this sound in my car about six months ago. Very annoying but didn't want to waste my time with the dealership. I've just been living with it. Now I found someone on FB complaining of the same noise. I would describe it as an "electronic buzzing" under acceleration, like fluorescent lights - also kind of sounds like crickets. It happens under acceleration only. Doesn't happen if you rev engine in neutral. Mine is 6MT and his is 10AT. First video is mine, second is his. Cadillac tried to tell him the issue was the fuel pump, which they replaced and it made no difference.

Any thoughts?

 

[Seth]

Hello all - this sound is driving me crazy. I hate it. It makes me not enjoy driving the car. Can I get some confirmation that this is not normal? A couple months back they first told me it was something to do with the amplifier (?) so they replaced the amp and it made no difference. Then they switched their story to "oh it's the fuel pump it's normal" ... it does not sound normal to me. I hate it. I have COVID and I'm grumpy

 

[NewCaddy]

It’s not a normal sound effect.,dont’t hear it with my 6MT.
Did the FB person share w/you any feedback from their dealership?

 

[Seth]

It’s not a normal sound effect.,dont’t hear it with my 6MT.
Did the FB person share w/you any feedback from their dealership?

Thank you for the response.

Unfortunately his dealership couldn’t fix it and he ended up getting rid of the car, I don’t know the exact story - sounds like the dealership bought it back.

 

[99sport]

Is it all the time or intermittent? (I'm not sure from the videos which noise you are referring to)

 

[Aaron4BW]

Sounds like it gets faster as the rpms rise, so it can be the hpfp. It is on the driver side against the cowl, but I have a 6mt as well & have never heard that noise. Maybe have a friend rev the engine up slowly as you are outside with the hood popped & take a listen.

 

[Super Saloon]

I can’t listen to the sound right now but have you tried driving with you key in your pocket v the designated key area? The only buzzing sound I noticed was also under acceleration and it was coming from the key ring when the key was in the holder. I took the ring off the key and the problem is solved.

 

[Seth]

Is it all the time or intermittent? (I'm not sure from the videos which noise you are referring to)

It's intermittent and more prominent with throttle input

Sounds like it gets faster as the rpms rise, so it can be the hpfp. It is on the driver side against the cowl, but I have a 6mt as well & have never heard that noise. Maybe have a friend rev the engine up slowly as you are outside with the hood popped & take a listen.

I will try this! Thank you

I can’t listen to the sound right now but have you tried driving with you key in your pocket v the designated key area? The only buzzing sound I noticed was also under acceleration and it was coming from the key ring when the key was in the holder. I took the ring off the key and the problem is solved.

Always drive with key in pocket. Thank you though!

 

[DCV]

That’s a weird noise. On one of my 350’s, the rear cylinder block plate would make a weird sound right at 4K rpm or so. That’s the plate that seals off the rear of the engine to the bell housing. I had to have it replaced.