Posted by Peter on February 18, 2002 at 00:00:43:

In Reply to: 89RR Low Rough Idle, Popping and Loss of Power posted by Hatari on February 17, 2002 at 11:12:50:

Loud rattling noise in the catalytic convertor means the substrate has disintegrated probably sending particles into the muffler and blocking it.

This would certainly account for lack of power, rough idle and overheated plugs as one bank has a massive restriction in the exhaust.

Disconnect the cat that is rattling and check idle speed and if brave enough take it for a run.

If you can measure low positive pressures, disconnect the O2 sensor and fit the low pressure gauge. Maximum back pressure should be no more that 21 kPa (3 psi) at 2000 RPM.

Peter