EGR rattle?

[Steve D]

I've searched but can't seem to come up with anything.

At highway speeds and mid- to high rpms (~3k), with very light throttle there is a loud rattling noise. It isn't at a specific rpm so I don't think it is a harmonic rattle of a heat shield or exhaust clamp.

A lift off the throttle or adding more pedal makes the noise go away.

Before I throw some parts at it, does this sound like a failing/failed EGR? My OBD-I truck isn't throwing any codes.

 

[Rivman1243]

Is it pinging?

 

[Steve D]

No, definitely not pinging. It happens under very, very light throttle.

 

[NLXTACY]

Heat shield loose perhaps

 

[Steve D]

Heat shield loose perhaps

I thought the same but it doesn't seem RPM dependent. I'll poke around and double check that though.