Recently I noticed my 01 Windstar was missing a little while driving. One day it began running very rough and the check engine light was flashing. Autozone's computer said that cylinder 2 was missing, so I replaced the coil, plugs and wires. The cylinder 2 plugs was VERY fouled and several others had a lot of carbon build up. It ran great for two weeks after the tune up. Now it starts rough, then idles smooth. When I start driving, it's fine for a few blocks, then when I need to accelerate it bogs down like I'm driving in mud. It will occasionally almost stall when at a stop. Sometimes, if I keep on the gas, it seems like something breaks free and runs OK, only to do it all over again. I noticed the other day, after a test drive, a loud popping noise and saw the catalytic converter was cherry red. Two different muffler shops have told me that it's not a problem with the cat YET, but is instead that unburned fuel (caused by either my engine running rich or missing) is dumping into the exhaust. It also idles rough for a moment when the engine is under load, like when I turn the A/C on, then it smooths out. In general it does not appear to be missing, so running rich seems to be the obvious cause. As I stated earlier, I've done a tune up, but I've also replaced the PCV, the manifold gaskets and bolds, throttle position sensor and fuel filter. Fuel pressure with the key on, without the engine running is 0 and 32 psi engine running at idle. The 32 is within range, but I'm not sure if there is supposed to be some pressure with just the key ON. It throws NO CODES. I took it to a local shop who had no clue. They said that maybe the intakes were clogged and wanted to charge me $600 to clean them. I'm at a complete loss and there are too many things that could cause my engine to run rich to keep replacing parts, but I've got to do something before I also have to replace my cats, which will run me $900. Please some advice.