This video describes a simple fix to a No. 4 cylinder misfire in a 2013 R/T, with 150,000 miles. The owner took his Challenger to two clueless shops which replaced the coil, spark plugs and MDS solenoid. All of these repairs did not fix the problem. The third shop, in this video, did some diagnostic tests and determined that the problem was a corroded connector to the ECU. The moral of the story is to take your Challenger to a competent shop.
That two shops failed to remedy the misfire is unfortunate for the car owner. In fairness however, replacing a plug, a coil and even an injector in response to a cylinder 4 misfire is going to result in a remedy the vast majority of the time. Unfortunately, these components too often test adequately but don't function properly. Under these circumstances replacing the MDS solenoid could also be viewed as a reasonable next step (suspect that shop also discovered the untimely MDS activation). Danielson had the good fortune of knowing which parts had already been replaced in attempting to remedy the misfire and due to it's unlikely cause may never again have the good fortune of correcting it by unplugging, cleaning and reconnecting the ECU (even he was giddy with surprise at the outcome and may suspect an ECU replacement is going to be required on this same application sooner than later). These forums are invaluable to us non-professionals performing our own maintenance and repairs. Good find Tom.
You're funny. LOL I am surprised we all made it through life without Google, and YouTube for so many years.
A while back, I had a CEL that read out a code for a Cylinder 3 misfire. Naturally, I figured I had a coil pack going bad, so ordered one from Rock Auto, replaced it, and oh crap - that didn't fix it. So I put the original one back in, but I switched it with cylinder 1. Same problem, cylinder 3. So I switched the spark plugs. Son of a gun, the misfire moved to cylinder 1! Those plugs looked fine to me. Barely even dirty. Got 2 new plugs, replace the ones that were now in #1, and problem solved. It really surprised me that a plug would go bad like that, especially these days. Car has only 76,000 miles. I thought plugs were good for 100,000 plus. Guess the moral of the story is "swap stuff around until you figure out exactly what the problem is".
At 76K I would have replaced them all. I usually don't go along with manufacturers pushing extended life.
Regarding failed spark plugs: I've had two fail where the center electrode would move and come in contact with the ground electrode. The failure was not noticeable unless you moved it around and turned it upside down.
Use this gapping tool on an iridium plug almost guarantees center electrode movement (not in a good way).
