Hey,

I posted the same thing last week and I got all the same answers, but this is what I found out...I removed the heat shield on the exhaust manifold and saw the biggest crack I've ever seen. I researched it a bit on d-series.org and it seems like this is a common problem with the d16's. I'm waiting for a new header to come it, but I had to do some experimenting to be sure. I mixed up a batch of JB weld and filled the crack the best I could (atleast what I could see) Sound went away, well, until the JB melted off and left the smell of some bad poonaner. Anywho, It's just something else to check for.