Now I'm thinking my problems related to yesterday's loss of power is a catalytic converter problem.

Here is my thinking:

1. I was working on the exhaust pipe (I could have jarred something loose?)
2. the problem was a loss of power under load.
3. a high pitched whine was coming from the area around either the exhaust manifold or the valve covers. It sounded like a teapot whistle when under load.
4. the car idled fine, the tach didn't jump, it didn't knock, it shifted between gears smoothly, but under load the car had no power.


What do you think?

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1991 740 B230F 140K miles

Removing the test port plug will substantially affect, but not completely fix, the lack of power under load.

Well I was right, it was the Cat. It was partially blocked. My mechanic just called, and gave me the news. He said I had 2 options....$40 bucks or $400 to fix it.

I won't tell you what I choose, let's just say my SUV isn't the biggest polluter in the family now.

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1991 740 B230F 140K miles