O2 sensors behind the cats do not control engine functions at all, only monitor that the cats are working properly. Have you done typical tune up maintenance (plugs, fuel filter, etc.)?

Did you pull any codes for misfiring?

DL

Changed fuel filter 2000 Kms ago. No codes showing. Does not misfire, just a slow idle in drive.

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Vern Lowe

Plugs are 4+ and were changed 52,000 Kms ago. Will try changing again.

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Vern Lowe

Try changing plugs to the OEMs. Many people have reported problems with ideling, misfires, etc. after going with the aftermarket Bosch +2 and +4 plugs. No one knows for sure why, but they cause strange problems after being installed, but often not right away. Search the forum for spark plug issues and you will see what I mean.