Rattling on my 09

Just had the egr valve/hosing replaced, to get into it and hear a rattling sound when I accelerate. Goes away when warm. Ideas?

 

Does it sound like metal tapping on metal or an engine ping? Faulty EGR can cause an engine rattle most noticeable under load when cold, but you'll likely get erratic idle and check engine light with it, and since you just had a new one installed... EGR tubes have a metal heatshield hose clamped on them. If the mechanic didn't tighten the clamps enough, the shields can rattle on the metal EGR tubing. Tubing expanding when hot might be causing it to go away.

 

Not a tapping, definitely more of a tin rattle. Doesn't really sound like it's the engine area making the sound, but I hear it when I step on the accelerator. Didn't hear it Tuesday when I picked it up. Valving was replaced Friday, the old one was apparently clogged shut. Rattle noticed after that.

 

If it sounds like it's coming from under the Jeep, might want to check the catalytic converter. Check the cat heat shield to make sure it's not loose. Clogged egr valve would have caused excessive exhaust temp which may have cracked the honeycomb inside the cat which will cause a rattle most noticeable on acceleration, but can go away when hot.

 

I had a rattle in my 08, could never figure it out, until one day the mechanic was working on it, there was some kind of shield around a part of the exhaust, when he removed it, it had a rock in it....