Join Date: Feb 2018Posts: 161Garage

Pulling a wire will set a code, and when a code (any code really) is set the PCM will disable the MDS system until fixed.

MDS shuts down 4 cylinders to save fuel.

Tuner can be both. Tuner that looks at logged data and adjusts files to improve performance (human)

Tuner that allows for replacing of factory calibrated settings to enhance various items. Typically you have to have one before a Tuner (human) can adjust it custom like.

Join Date: Nov 2015Location: Dallas, TXPosts: 612

"...the failure was gradual over a long period of time."

This gives the impression that the damage was spread out over multiple OCIs, which lines up with what I had previously envisioned as well. However, I can think of at least one instance of a similar failure (on a Challenger) where it was much more sudden. The owner in question mentioned the damage occurring so quickly that he noticed it was running rough one morning on the way to work, and before he could make it home, it died and wouldn't run again. Now, in his case, I know they ID'd the lifter freezing as the problem - it froze and ate the cam up. Do we know if the same thing occurred here?

The reason I remember that Challenger owner's story over many others I've heard is that I previously believe keeping an eye on thing via UOAs would be sufficient to catch any failure before it got to the failed point. However, the Challenger owner corrected me with his story, as he had been doing exactly that (getting regular UOAs), yet his failed in the middle of an OCI, and so he never had a chance to see it coming.

Just one more data point to add to the story...