This has been intermittent but getting more frequent and today I was stuck for a good 10 minutes before it decided to allow me to start. I have other lock problems which I am living with (343,000 miles on vehicle) but really don't want to scrap the car over this. I have tried opening and closing the door, flexing steering wheel, etc. It seems the key is just not engaging when put in.
My key sometimes won't turn in the ignition. on 2002 Mercedes-Benz E320
replace the ignition barrel-QUICKLY.If it totally carks it, you gotta start with a chainsaw to get it out.Buy a cd-rom manual for your model. they're cheap, I bought mine off the net, even though I am licensed mechanic. If it's the same as the earlier ones,unscrew bezel surround off lock, turn they key to accessory position, i think it is, insert smallish probe or pin into hole in the thing and pull it out. Probably gotta buy one from dealer so take crutches so you can get home after he removes your left leg to pay for it. Not a big job if its the same as mine. This happens to a few of the models, so don't worry. It's an excellent system, but they do wear out.