Texas.....give this guy a hand. You described a lot of things...and there are some possibilities we all could suggest you take a look at. Problem is, none of the things I will mention did your mechanics even look at. So, I would find new mechanics 1st off. There are a host of things that would cause shaking, missfire, and flat dying. How many miles are on the car would help. If you told me I missed it. Here are some common problems that can cause shaking and dying. The crankshaft position sensor. A very common problem with these cars. I would replace this 1st. Vacuum hose leaks, gaskets around throttle body, air intakes....all can cause rough idle as well. You will get a ton of response here...and maybe someone in Texas will steer you to a good mechanic.