Oil Pressure/Temperature guage????

[flynrider]

Since fuel mixtures at idle are typical lean for emissions compliance, my guess would be that the ECM probably enriches the low rpm fuel mixture to provide additional cooling.

If the oil temp is already at 342F I'd consider it seriously overheated, so I'm not sure how much good it would do.

Note: Almost all oils (synthetic or dino) will begin to experience thermal breakdown before getting to 300F, so if you ever see your oil temp light come on, your next stop should be your garage for an immediate oil change.