Passat (B5) :: Engine Seems Sluggish On Startup - CEL Popped On

First, let me address existing issues with my VW 2000 Passat:

- My mechanic has told me that my turbo is slightly cracked and oil is dripping from it as I was not allowing my car to warm up/cool down after driving. He said that the damage done was not much, but I should allow my car to warm up/cool down from now. This was back in September/October, and I have been allowing 1 min- 1.5 mins for both warm up and cool down as I tend not to drive more than twenty miles in a single trip.

- While checking the oil level roughly two-three weeks ago, about 100-150mL worth of synthetic oil spilled into the the tube where the dipstick goes. No effects were noted in the next week.

Now, my problem is within the past week starting up my car has been a strange ordeal. Immediately upon ignition, until about 3-5 seconds after, the engine seems sluggish - similar to when the battery is low from leaving the lights on overnight, for example. However, the engine has had no problem actually starting. Once it starts it acts normal, but soon the engine makes wheezing noises as if gasping. Accompanying the noises is a strange alternation in my lights between full strength and a dim strength I have never encountered before. This wheezing, and the strange light effect, last for roughly 1 minute. This has all been consistent for the past week. While driving home after work today the CEL popped on.

It is worth noting that the last few weeks have been especially cold, with the temperatures at which I'm starting my car being from 5-18 degrees Fahrenheit.