Intermittent rough running dodge ram

I have a intermittent problem since October 2004 with my 1998 Dodge Ram 1500 pick-up truck with a 5.2 magnum V-8 engine that now has 97,000 miles on it. Beginning at 73,000 miles, upon starting the truck, it would idle rough, the check engine light would come on, and when driving over 40 mph it would shake and shudder severely.

Over the period of five years it has been to the local Dodge dealer many, many times since the problem started and the following work has been performed on it;

A A complete tune-up,

B performed a fuel injection service, including cleaning the throttle body and setting minimal air flow, also checked the A.I.S. motor

C replaced the intake manifold gaskets,

D computer diagnosed misfires in cylinders 2,5,7 & 8 and replaced fuel injectors,

E at 92,861 miles replaced the cylinders heads because they were diagnosed as being cracked.

Last week, the problem started again; rough idle, check engine light would come on, and when driving over 40 mph the truck would miss, causing the truck to shake and shudder. Again took it to the dealer and the computer said it was a misfire in cylinder #7. The dealer found nothing wrong when they started the truck.

Can you give me any suggestions what the dealer should look for to solve this problem?

Does this engine have an individual coil for each plug? If so, were they replaced?

Were the plug wires replaced?

What was replaced during this ‘tune up’?

If a distributor cap and rotor weren’t replaced with this tune up, I’d get them done. Same with the spark plug wires. This vehicle has a single ignition coil which could be failing—or the wire from the coil to the distributor cap could be failing. Does the vehicle run worse in damp weather?

Only one coil

The wires were replaced twice

The dealer called it a complete tune up…wires, plugs, distributor cap and rotor, cleaned injectors.

Want to hear a weird one - try changing the battery. If you have another just swap them and see if that does anything. You wouldn’t believe the problems I have heard of with these trucks because of a battery that does not have the correct voltage. The computer just goes screwy. I know a guy that spent 5 years and over 5 grand trying to get the auto trans in his HD Diesel Ram to work right. Dealer was stumped (but didnt refund any moola). After one of the two batteries failed he replace both of them and the tranny worked perfectly afterwards. Took the bad battery apart and it had a bad connector between the cells. Just one of many stories.
Hey its a cheap test.
Another thing is that my 94 has had similar problems because of the weird fuel pumps on the 94 and 95 models. For some reason after the fuel level falls to around 1/4 I have the same problems as you describe. Check my posting for ‘94 Ram 1500 fuel pump problem’. The thing works fine after filling the tank. Maybe you have some type of fuel pump problem.
Good luck.