I have a subaru outback - whenever i accelerated, there was a rattling noise. The dealer told me that all i needed to do was remove the heat shield - is this what you recommend, or wouldn’t it be better to tighten the shield so it doesn’t rattle?
Usually I try to repair them with either self-drilling screws or by welding. But sometimes there’s nothing left to screw or weld to. So you take it off.
Heat shields are often a clam shell design. There’s a top and bottom half. You know why? Converters normally get very hot and are often tucked up into a spot under the car with minimal clearance. it’s a risk to start a fire underneath the car when/if you park over vegetation as well as the car itself if the heat shield is removed.
It’s possible for them to get really, really hot if something goes wrong with the amount of fuel being injected (which is not all that uncommon of a problem) and the risk of a fire goes WAY up. I had a truck where the coolant temp switch went bad and it was running really rich. Even with the added clearance of a truck and all the parts in place, it almost burned down. The seam sealer was bubbling and smoldering and even the carpet inside the cabin was very hot to the touch. I was lucky. Don’t let them remove it, get it fixed.
I agree with TwinTurbo. Subaru did not include that heat shield just to waste their money.
Clearly, it was put there for a purpose–either to protect adjacent components from the excessive heat of the exhaust system, or to prevent the car from starting brush fires when parked in tall grass. Have it repaired by an independent mechanic or by a muffler shop if your dealership isn’t inclined to deal with the problem.
I too had this annoying rattle on my '02 Outback, I solved it by using a stainless steel adjustable hose clamps. They are used on swimming pool hoses and several can be put together to form a longer length. Easily obtained in any hardware store or section of larger stores. The screw adjusts the length and tightens the heat shield quite well. They don’t cost much so you could put several sets on, are very sturdy and seem to solve the problem once you gain access to the area. You only need a screw driver or the proper sized socket wrench. Good luck