Did the stealership ever remove and clean the TB as well as the IAC Tip and passage?
This will require a new gasket and you have to be careful not to snap off the nipples for the coolant lines.. I think they are plastic, Could be wrong memory isn't serving me on the 3.1 right now..
But a lot of Idle and hard start issues could be Throttle body related...
Once its all back together, and you reconnect the battery it may take a handful of seconds for the ECM to figure out how to idle.... after it warms up you'll want to take it for a spin above 40 mph in TCC lock so that the ECM will relearn the IAC position..
Also how does the car run once shes moving?
Does it start easy in the morning?
Do the issues only happen when the engine is warm? Or does it happen all of the time no matter what?
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