Knocking under the car...

[Emily]

My car has developed yet another baffling noise.

There is a knocking noise under the car when I accelerate. It is only when my foot is on the pedal. If I am going 60 with my foot on the accelerator it will knock, I remove my foot, maintaining my speed, and the noise stops. It is felt though the floor board. I noticed it first when I was in the passenger seat and could feel it in under my foot.
I have no idea what it is. I am going to have to take it to a shop but I wanted my bearings before going.

Any ideas?

Has anyone else had this happen?

[Wiscon_Mark]

Is this a metallic rattle, or more of a "knocking on the door" type noise?

If it's a metallic rattle, it's heatshields.

If it's "knocking" (not to be confused with engine knock) then it's probably valve clatter, or maybe piston slap. Neither are a horribly big deal, and an oil change would probably make the noise go away.

the reason I suggest heatshields is because it's very common and you said it's on accleration, and most people hear valve clatter/HLA noise/Piston slap at idle.

[backpack09]

Check for small furry creatures.

[d1giPhux]

I get heatshield rattle like crazy.. but you wont feel that on the floor.. or feel it knocking at all.. its more of a metal rattling sound when you accelerate.. so its probably not that.

[SilentRacer]

is this the noise?
https://sl-i.net/FORUM/viewtopic.php?t=6071