94, VR Executive - idle low & blowing smoke

[HRT05C]

We've got a VR executive, she's a little beaut hitting on the 280,000k's but we're having trouble with her idling really low to the point she's on the edge of stalling on start up, car gets the shudder going. And she's blowing a bit of smoke too. Give her a rev up and she settles down. Just in the last week replace Body Control Module & Regulator on the alternator. Any suggestions on where we could be looking for repairs?

[hako]

Could be the coolant temp sensor playing up telling the ECU that the engine is cold all the time resulting in a rich mixture and blackish smoke. Might pay to clean the throttle body as it may be gummed up.