Dreaded Previa Whistle AND CEL code 71 cured with new muffler

[pdgizwiz]

My '94 N/A Previa has whistled since I bought it about a year ago. It has also had a Check Engine Light on, due to code 71, related to EGR gas temperature. I have been putting off both a new muffler and cleaning the EGR port all this time. Finally I got around to putting a new muffler on. The whistle vanished, as I'd hoped it would. But soon afterwards, I noticed that the CEL had gone off as well. A pleasant surprise, to say the least!
The new exhaust seems a little louder than the old. I was a bit disappointed by that at first, but the unexpected CEL cure more than makes up for it.

The exhaust "silencer" I bought is a Bosal 284-285. One of it's quirks is that it has a support post welded onto the pipe near the flange that attaches to the cat pipe. The stock setup involves a separate part that integrates the support post and a nut plate on the front of the flange. I guess that it's common to torch the nut plate, thinking that the welded nuts are seized with rust. I took the lazy approach and, rather than cut the post off of the new pipe, I used it in the rubber mount and found some nuts to replace the nut plate.

**update** Code 71 returned a week later