ml320 engine missing-Key question

1-Here's the deal. My 99 ML 320 will start to miss very bad sometimes when first started. Never when already running. At first i thought there was water in the line as it seemed it was not getting enough fuel. I added a bottle of gas line water remover and it worked fine. However at random it will still do it. When i have the problem, it will start fine but under load (in gear) i can not accelerate over 30mph and missed badly. If i stop, turn off key, and restart, sometimes it clears up and i'm on my way. Sometimes i add a bottle of water remover, restart and i'm on my way. Not sure if there is acxtually something in the fuel or just actually resetting by turning off key.
I have done the fuel pump upgrade. Is there an easy drain for tank? The last code reading i got was "fuel rail" and CEL is on.

2-i dropped my key and now will not work. checked batterys and have tried reprogramming per instructions found here on the forum. Also, when opening by key, alarm sould sound until you get the key in the ignition. Now alarm does not sound when i unlock door and can only open 1 door, not all four with key. i have to get in and unlock by button inside. Any suggestions?

Thanks for the help.