Engine seems to want to cut out.

Ok, here is the problem. A few days ago I changed the plugs and wires on my 97 4.0L. After I got the new plugs and wires in I started it up and it idled rough for the first second or two and then evened out. So I figured it was OK. Turned off the engine and went to clean up my tools. Came back to the Jeep and tried to start it. Nothing. It would turn over, but would not start. Changed the plugs again. Started up, idled rough for a second or two and then evened out. I drove it to my mechanic just in case it decided to not start again. Got the fine, Jeep ran fine. Turned off Jeep and tried to start it again and once again nothing, didn't even turn over. Mechanic came out and wiggled the battery wires a little and the Jeep started, but rough again. He thought I might have water in my gas, so I went and got a fresh tank of gas. Now the starting problem is gone, but a completely new problem has shown up. Now, while I am driving the engine will cut out for just a moment and the Jeep will lurch. The problem is that this is not a regular thing. It happens at completely random times. I can be idling, accelerating, or at wide open throttle and every once in a while it will miss. As of right now I have three theories for why this is occuring. Either I still have water in my gas and every once in a while I will get a shot of water instead of gas. Or my distributor/coil is going bad making only one cylinder miss at random times. Or finally, my auto tranny is somehow screwing up and trying to shift or is catching when it shouldnt. I cant really tell. I have noticed that sometimes when the engine starts to miss my tach will read a drop in RPM and then it will imideately shoot up to about 3000 RPM's higher than the engine is going and then will drop back down to proper RPM's almost immediately. This leads me to believe that perhaps the coil or distributor is going bad since the tach runs directly off them (as far as i know). But then again, it seems like the engine wont do it as much when there is a fresh full tank of gas in the Jeep. Could all this be related, or are all these problems completely incidental. Please Help, I need my Jeep to be running well before I leave for College Thurs. morning. Thanks in advance.

I had a lurching problem and found that my CPS (crank position sensor) wire lead had been touching my exhaust manifold , melting the plastic off the wires. I moved the wire off my manifold and it didn't lurch again. I replaced it when I got back from camping.

Sounds electrical, I have had a similar problem and it was the crank position sensor. But what sounds wierd to me is that this all started after you changed plugs and wires. That would make me believe that it might be that you got a bad plug wire . It might be broken inside the insulation (which I have seen many times) . This would cause the motor to run fine most times but every once in a while it may become diconnected due to motor torque on acceleration or running over a bump in the road or whatever.This would cause the motor to not fire on that cylinder and it may only be for a split second. I would try a new set of wires first before getting to involved with anything else.ALWAYS TRY THE EASIEST THING FIRST!!!!!!!
Good Luck
J

I don't believe it's the CPS. I've had one of those go bad before (on my 87 Cherokee) and it never caused it to lurch. When the CPS went out on the 87 the engine would simply shut off and wouldn't turn on for about 30 min. The bad plug wires are a possibility. I may go buy some new ones and try that. It would make since for the wires to be bad since they are the only things I changed except for the plugs. I'll try that later today. Right now I have to go reweld my exhaust on since it broke loose last night while I was "Baja" racing down some dirt roads.