Knocking noise under the hood

I have a 2005 Chrysler Pacifica. It has a “Knocking Noise” under the hood when driving. It sounds almost like something is moving around. It happens when you touch the gas pedal, at any time accelerating, but not all the time. Of course, the dealer found nothing wrong, but it is getting worse. Any ideas?

Carl 246

Is it just one knock per acceleration or more of a continuous knocking while accelerating?

Did they check engine and transmission mounts, for wear, damage, and/or clearance, do you know?

Making sure it’s clear in front of you, can you make it happen with car stopped, foot on brake, in drive, by gently pressing/releasing gas pedal?

carl 246,

Are you hearing one knock per acceleration or continuous knocking during continuous acceleration?

Did the dealer check the engine and transmission mounts and the necessary clearances associated with these parts?

Sorry about repeating myself. It’s a long story.

It’s just one knock when accelerating, not continuous. It will not happen sitting still, it happens when the tires start moving. I have checked it sitting still pressing the pedal. I don’t know what the dealer checked. I wondered if it could have something to do with the tire movement somehow as well. It will do it sometimes gently backing or turning, say in the driveway.


You say the dealer found nothing. Did they hear the sound?

Since it is getting worse, this is probably one of those cases where you need to go along on the road test with the dealer advisor/tech person and be sure they are hearing what you are hearing.

If you have done this, then you probably need to try a different repair facility to go for a ride with.