Diagnosed an annoying noise today.

Since I purchased my Taco almost two months ago, I've heard an annoying squealing noise.

The engine is almost always at normal operating temperature when I notice the noise. I really hear it when the A\C is running, or when I rev the engine just past 1K RPM and the RPM is settling back to idle.

The squeal sounds like a small supercharger, it'll spool up and then spool down as the RPM settles back to idle. I initially thought that I had a bad idler pulley bearing or two. I ruled them out after listening to them with a stethoscope.

I was hearing the noise more from the transmission area, and thought that it might be the pilot bearing. So I figured I would wait for the noise to get worse, or take care of it when I replace my clutch.

Then this morning as I was removing some things from the passenger side when I got to work, I heard what sounded just like my nemesis when I closed the door. When I got home, I kicked on the A/C and climbed under the passenger side to listen for the noise.

At first I still thought it was coming from the transmission. As I crawled further, I started to hear it more from the catalytic converter area. I went and grabbed a pry bar and started to put some side pressure on the cat converter shield. BINGO, the noise disappeared.

Tomorrow I'm going to remove the shield and see if I can find exactly where the contact is being made and fix it, or I may just leave the shield off. Either way, I found the stinkin' noise.