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mikefocke · 10-31-2009, 01:05 PM

more often a sensor or wiring.

The diagnostic to determine if it is really a cat is to replace the O2 sensor and then see if the problem goes away.

See if you can swap O2 sensors and does the problem follow the sensor or remain where the questionable sensor was? Swap pre-cat sensors first.

Any history of AOS problems? Checked the intake tubes for oil?

10-31-2009, 01:05 PM	#2
mikefocke Registered User Join Date: Aug 2005 Location: Sanford NC Posts: 2,537	It is seldom the converters themselves more often a sensor or wiring. The diagnostic to determine if it is really a cat is to replace the O2 sensor and then see if the problem goes away. See if you can swap O2 sensors and does the problem follow the sensor or remain where the questionable sensor was? Swap pre-cat sensors first. Any history of AOS problems? Checked the intake tubes for oil?