Knocking Noise Not From Engine

[Billy1234]

It only happens after I drive the car around for a lil bit and it does it when I'm going straight or turning and gets louder when I accelerate and it sounds like it's coming from center underneath the car

 

[Real time recon]

Exhaust Loose baffle .Loose hanger ?

 

[Blandnuts]

Auto or manual?

In gear and out of gear if you rev it up?

 

[Billy1234]

Manual both

 

[stpete]

I've had bad AC compressors sound pretty terrible. Maybe another accessory.

 

[Blandnuts]

Put the car on jacks after you warm it up. Since it does it out of gear, get a helper to rev it up while you narrow down the exact location.

Also, does the sound go away if you put slight pressure on the clutch pedal?

 

[Billy1234]

The sound doesn't happen if the car just sits warms up and u rev it and turn the wheels. The sound only happens when I'm driving and after 10 mins of driving this knocking noise starts happening. And I don't have ac in the car

 

[Real time recon]

Bumps in the road.Loose or missing exhaust hangers/clamps

 

[stpete]

u-joints?

 

[General karthief]

This one's gonna be tough.
Start with the exhaust, metal expands when heated, but you knew that already, with that in mind, talk it for a ride and when the noise starts take it to the house and jack up the rear end, use jack stands of course, we can't have members get'n squished, start it up and put it in gear see if it rattles, check exhaust connections and hangers, then the drive shaft, trans mount things like that.
Let us know what you find or don't find.

 

[Billy1234]

Will do I let u know wat it is

 

[Billy1234]

Haven't found out the issue yet but I just found a 1/2" pipe going along the exhaust pipe and sitting up against the catalytic converter so that might be getting hit up against it making the noise I do not know

 

[Billy1234]

Here is a clip of the noise cause I'm still not sure what it is.
View: https://www.youtube.com/watch?v=tgJwEdwLSLw

 

[Real time recon]

Watched the video. My Answer is still the same.Loose/broken/ missing exhaust hangers.

 

[Blandnuts]

I would put it on jacks and grab a pry bar and touch/push on exhaust to rule it out (from headers to the end of the h-pipe). But, since it does it at idle/not moving, I think Real time is on to something.

Also, check your transmission mount and engine mounts.

 

[FoxMustangLvr]

Is your exhaust or anything else hitting your driveshaft? Also, the 1/2" pipe may be your smog pump pipe, is it connected to anything?

 

[Billy1234]

It was just a bad catalytic converter, thx for the help

 

[Steel1]

Darn! That was going to be my guess when I saw the cat in the video. Glad it was nothing serious.