Doing some research, came across the thread....my '22 Telluride w/ 10k miles is currently in the shop for a bad coil pack. I feel like the issue has been ongoing for a while....is this something that could go on for months or is that unlikely? Trying to assess if the previous jerking I took in for months ago might've been related.....
I do agree that thousands of new Tellurides out there, you're bound to get a bad part here and there.
Just to add a little validity to this thread from the repair side of things. When I had my BMW shop (small 2 technician specialty shop) we would sell some 60-120 pencil type ignition coils per month. Just like lightbulbs all installed the same time same/circuit, they have a life cycle. If one went bad, we would replace all 4, 6 or 8 (number of cylinders) at the same time. Why? Because most usually the other ones would start failing in short order. PITA for my customers and just made me look bad because I was saving the customer $$$. Comebacks (having to return for the same or associated repair) I never liked or wanted.
Longer version:
Pencil type ignition coils or more commonly known as Coil On Plug (COP) have been around for some 25-30 years. Benefits are much better charging/discharging (what actually makes the spark at the plug) and ability to much faster control the individual ignition timing at each and every cylinder, during each combustion cycle. Also having the ability to be able to shut down an individual cylinder (also the corresponding injector) for the misfiring cylinder after a prolonged period (A OBD 2 requirement after Jan. 1995) so that the misfiring cylinder NO longer spewed raw fuel down the catalyst and the tailpipe.
The downside of the COP system is twofold:
The coil sticks down a long and very hot tube that is the spark plug tube. There it is surrounded by all of the hot coolant (cooling jackets are immediately adjacent there) and very little opportunity for each coil to properly dissipate heat. It's also capped off at the top to prevent any water ingestion.
Then there's the manufacturer (KIA or whomever) that wants Delphi, Toyoda, Mitsubishi or whomever, to make these things available to the Mfr. for a paltry $3 each! There's going to be a high number of failures per 1,000-100,000 whatever the metric is.
Older cars had one or two, three coils mounded on the firewall with ignition wires to each/every cylinder. The coils lived in a cooler (think about that for a moment, under the hood is MUCH cooler than down the spark plug hole!?!) environment and therefore lasted the lifetime of the vehicle and much past the due by date.
Also old and tired spark plugs make each ignition coil work very much harder on each and every combustion (firing event) stroke. Tired and old spark plugs with twice the specified gap will see each coil have to produce some 8-12KV to jump the wide gap. Whereas new plugs would normally see some 4-6 KV needed to fire each plug at highway cruising speed. More KV = more work = more heat = shorter life.
So there you have it, way much more than you ever knew before (?) about coils/ignition systems.
HTH?
