bad noise under acceleration and then sut down
was like pre ignition. next hard acceleration bad noise and sut down. shakes bad and loud knocking sound. no codes stored.
Possibly a plugged catalytic converter. I'd start there. I know there's a lot of differences in years, but it sounds similar to something my '95 Bonneville did near the end of its life. After some cool down time it would behave itself again until the next time I accelerated hard. I think it was the computer doing weird things. It was a high miler and fortunately my son used it to push a much slower vehicle in a snowstorm, so I sold it to the nice insurance company and didn't have to fix it.
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