For those of you lucky enough to be driving DP's this is not for you except for entertainment value. I purchased my 2nd Barth almost one year ago in Seattle. At the time of purchase it had new a new tune up including wires and was ready to roll! It's 454 with 400-hydroamtic trany. My maiden journey was from Seattle, WA to Portland, ME in 3 days. I have since put 15k miles on the rig. But I diverge�One of the trips this year was back and forth across the country in June and the first week in July. Now for the good part:

About 1500 miles (and 3 days) from home I noticed that the rig was running about 30 degrees hotter then normal. Since we had just run through the biggest pile of mosquitoes I've ever seen in Canada and slowing down 5mph reduced the heating problem I figured I'd blast the radiator when I got back. While passing Niagara Falls it skipped once and then again 600 miles later entering Maine. Odd I thought but we survived 9500 miles and 5 weeks pulling my 1984 diesel rabbit.

From that point forward intermittently and with greater frequency the rig started to run rougher and occasional backfire. I new from a compression test when I bought the rig that one cylinder was getting weak so I figured that this was really the route cause. I asked some of the experts on this site and took in all of the useful information and started working on it.

When I pulled the plug on the cylinder that I thought was bad it was fouled like I suspected so I decided to pull all of the plugs and do another compression test. WOW! Half of the plug wires disintegrated in my hands while trying to remove them. I replaced the plugs, wires, and added heat shields, and ALL IS WELL!

Now if some one could explain to my why bad wires would make the engine run hotter I�d like to hear it.

Simple physics really.

With a weak spark, and poor combustion, the fuel is NOT adequately converted into mechanical motion, and is burned creating heat instead.

That excess heat has to go somewhere....

Thanks for your input on this. I brought up the increase in operating temperature issue because that�s what lead me to the spark plug wires. I happened over a message on another forum that someone had left about his rig running cooler after changing the wires and no one could tell him why. It was just too coincidental for me that I was having some of the same problems.

The bottom line and what I want people to be aware of is that the increase in temperature was the first sign that there was a problem with the wires. In my case it occurred 1500 miles before there was any noticeable running problems. To be more specific: at 65mph you could see the change in temp., but at 55mph the temp returned to normal.