1985 Audi 4000 running rich at idle only

My 1985 Audi 4000 is running rich and rough at idle speed only.
I replaced the oxygen sensor and cat converter and checked the fuel injectors. Those parts seem ok now.
Any ideas or input would be appreciated.
Marti-
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vgf wrote:

Vacuum leaks?
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throttle switches probably have broken wires could be a faulty fuel distributor or your CO needs adjustment AFTER you check those switches. cold start valve may be leaking, but you said you checked the injectors. check for broken ground wires there too. Got a Bentley?
check and report findings
--
later,
dave
(One out of many daves)
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My thanks to Tony and Dave!
I still have a new ISV from years ago, will check that and do the stuff Dave suggested.
marti
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My thanks to Tony and Dave!
I still have a brandnew ISV from years ago, will check that and the other stuff.
marti-
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