My 06 E53/M54 has an odd problem.

When home in FL climate it struggles to start from cold, and once started I need to bring the RPM up a little for just a second and then the idle stabilizes.

Just did a road trip to Ontario for 2 weeks and the car had zero issues the entire trip. Started right up every. Single. Time.

We get down to around Georgia and now it's back to hard starts and poor idle. Every. Single. Time. (When cold. Once engine is hot it's good again)

New plugs. New CCV. New thermostat. New O2 sensors. New Intake Side Cam Position Sensor.

I'm wondering if the MAF could cause this? Or if there's something else I should look at?

It burns about a Qt of oil every 900 miles (now that the oil leak from the oil filter housing gasket has been fixed!) so initially I was wondering if it was just CCV leaving oil in the intake that needed to burn off before idling smoothly. But new CCV and no issues in cooler dryer climates for weeks. So thinking it's not an oil issue.

If the plugs weren't new and the problem didn't exist prior to changing the plugs I'd suspect those. But the problem has existed since owning the car. This trip up north just gave me more feedback to diagnose with in terms of climate and humidity.

It also continues to have an issue where it stalls (infrequently) at low rpm around corners. This issue also did not exist in the cooler climate.