My 97 has been making a heat shield like rattle when in D at idle such as sitting at a light. It's muffled and seemed to come from under the passenger's footwell. A month ago I thought I found it because I could duplicated it by slapping the coolant reservoir and it sounded the same, so I put a chunk of foam next to it. Nope, not the problem.
Doesn't do it in Park or neutral - something about the slight load and a warm engine idle.
Finally, I left the truck in D and the parking brake holding it and went over the truck. Found it to be the air intake tube that's inside the right fender where it is sheltered from dust, water and hot underhood air. It makes a sound that fairly replicates a loose heat shield. So I wedged a chunk of foam in there and it has been dead silent ever since. I'll work something out more permanent later.
Just in case anyone else has this....
DougM
Doesn't do it in Park or neutral - something about the slight load and a warm engine idle.
Finally, I left the truck in D and the parking brake holding it and went over the truck. Found it to be the air intake tube that's inside the right fender where it is sheltered from dust, water and hot underhood air. It makes a sound that fairly replicates a loose heat shield. So I wedged a chunk of foam in there and it has been dead silent ever since. I'll work something out more permanent later.
Just in case anyone else has this....
DougM