If I let it sit and idle for a long while the tick will go away sometimes. But once I drive it the tick comes bac help.
This is commom problem on higher mileage M113 engine which is what you have. How many on your car so far?
Also have you been changing the oil regulary, and used synthetic oil?
A while back I had a E430 with the lifter noise you describe. The only times I was able to lower the ticking noise is when I did two things: use high octange gase at least 91 and add 1 qt of Marvel Mystery Oil to the engine.
I have 192743 on it I change oil on time and yes I use synthetic
You don't think it's a bad lifter?
I think it is a bad lifter. The thing can run like that for another 50k miles. Unless you take off the head and rebuild it Which in my opinion is not worth it considering the miles.