My 98 5.2L all of a sudden is very hard to start after it has been driven. Starts great in the morning. Drive to work or to the store, let it set 15 minutes or more, and I have to stay on the key at least 5 seconds before it cranks up. I ran a pressure gauge on the rail sticking out from under the hood for a week. 50 psi the instant the key hits the run postion. It only bleeds down to about 35 psi overnight. After checking everything I knew to check, I consulted a buddy who worked for years as a mechanic at the Dodge dealership in town. He hooked his Snap-On computer to it as well as a fuel pressure guage. Everyhting looked fine. After not being able to find anything that way, we hooked a spark-checker in-line between the coil and the coil wire. First 3 or 4 seconds cranking over - no spark! Once it started sparking, it fired up. The cap, rotor, plugs, and wires are only about 6 months old, so I bought a coil and put on it. Didn't solve the problem. Suggestions? Other than the coil, what would have heat-related problems and cause it not to fire while cranking over for the first few seconds, then start once it begins sparking and run fine???

 

The crank position sensor acts as the "pick up" plate (HEP) for the distributor. If the coil isn't firing, that would be something to check.

 

I gave up and took it back to the dealer this morning. Handed them my keys, gave them my phone number, and said call me when it's fixed. I hate having to pay someone to work on my ride!!!