Running rough and trowing differnt codes.

Hi, I am the proud owner of a 2001 Mazda Tribute LX V6. The car has 137,000 miles. Let me start by giving some background on how I got to this point:
The car started running rough. I took it to a local shop and they checked the computer. The code indicated the #1 coil pack was bad. They replaced the pack and it ran ok for a day or so. It messed up again and showed the same code. He switched the pack again and the same code came back up several hours later. So this has been ruled out as the problem.
He recommended taking it to a dealer to let them figure it out. The dealer said a wire was broken and the cost would be $800.00 to fix. I took it back to 1st shop and they found and fixed a broken wire. Car now started stalling so he again gave up. Yesterday I was checking some things myself and found another wire (Grey w/yellow tracer) in the plug on the firewall broken. I fixed it and now car runs without stalling but it is still running rough.
So here are the systems now. Car has a definite miss but the engine analyzer said there is no miss. No codes are showing up and check engine light is off. The car is real sluggish. It takes 30 seconds to get to 60 mph. When you step on gas, rpm is at 4000 and car is only going 15 -20 mph. When you are cruising at 55-60 the engine will miss and studder. The car is also burning gas like crazy, I filled it up and it burned a 1/4 tank in 35 miles. This tells me I am running real rich.
Before I take this back to a dealer, has anyone ever experienced anything like this? I would really appreciate any help you can give me.