Cold engine = stalls Hot engine = rough idle

This car is driving me to drink. 1999.5 Newer Body Style 2.0L Auto. It all started when the coolant flange started leaking (the plastic flange on the back of the engine that is common to fail). Antifreeze everywhere so after I replaced the flange and took it for a test drive I noticed the speedo was not working. I kinda thought that something must have got wet from the antifreeze and started to corrode. Did a few searches on vwvortex and everything pointed to the speedo sensor on the transaxle so I took the connector off and cleaned both sides of the plug with contact cleaner (plastic safe). To my delight the speedo started working and everything was ok. A few days later I tried to start the car and had a very hard time. Actually for me to get it started I have to hold the pedal down and when I get it started I have to keep it revved and use two feet one on the brake and one on the gas then slide it into drive. Once I get it going and the engine temp comes up it runs better and will not stall when I stop but it does idle rough and drops down to about 600rpm usually it's around 800rpm in drive. The check engine light is on and the code is P0303 I think that is cylinder 3 misfire. The only other thing that is wrong with the car is I have a bad front driver's side door lock module. Seems that the switch that knows if the door is open or closed is ok because I can lock the drivers door with it closed but if I open the drivers door and hit the lock button it will not lock. The switch that tells the alarm that the door is locked or unlocked is bad and the alarm will not activate and the fob is not working. Any help with this will be very much appreciated. Thanks

bump for help

Problem fixed