I have a strange problem on my windstar... at the first run of the day or after a long sitting, the van starts and runs fine... the problem is that after it's had a chance to warm up and then go drive it again, such as going to the grocery store... the van runs really rough, almost to the point of dying (and many times does). Seems like it should run better once it's warmed up ----- anyone had this issue before? I have my theory about it... but am intersted to what you all might have to say and see if it matches. I've put a lot of time and money in this van fixing vacuum leaks, changing O2 sensors and DMRC valves and whatnot.... what's next?