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I have a bad Cadillac converter

I have a 1999 Chevy Z71 It is time to smog it. I have hooked it to a computer and it is telling me I have a bad Cadillac converter. I have two How do I know which one it is?

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  • drummond 15 Feb 28, 2009

    I have the same problem with my 99. When scoped, a problem with the catalytic converter shows up. It also shows O2 sensors are bad. The engine is missing on at least one cylinder and the air intake manifold might be leaking because there is a bit of foam inside the oil filler and where the valve cover exhausts into the air intake. Could the catalytic and O2 damage have been caused by the engine coolant mixed with engine oil venting into the carburation? Can it correct itself? I changed the distributer gear, rotor, cap, wires, and plugs, thinking that it just needed a tune up and that the gear was worn way too far for the computer to compensate the problem. When this didn't correct the way the engine was running, I looked closer and found the other problems. The O2 sensors aren't too expensive but a new converter is something to start saving for. Any help you can give would be appreciated.


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If one is bad chances are both of them will be bad. they would be the same age so your best bet is to change out both of them

Posted on Jan 08, 2009

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