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Cylinder 3 Misfire Corrects itself

My 2014 T&C with approx. 63,000 miles on it felt like it was running rough.

On Nov 28 the check engine light comes on- code is a misfire on cylinder 3. We bring it to our mechanic- he finds a rodent nest under the intake manifold (amazing because this thing gets driven A LOT), found #3 ignition coil defective, and recommended replacing spark plugs while he is in there (for maintenance). Clears the mouse nest, removes and replaces intake manifold, premium gasket set, ignition coil, and spark plugs; cleared code and says it drives well. I pick it up and still seems to run a little rough, but assume I’m paranoid and decide to drive it home and see how it does.

Next day, load kids in, start van, wait for hubby to get in and the check engine lights comes back on. Mechanic says bring it to Dealership, it may be a recall like on earlier years. (Spoiler alert- the recall was 2013 and older and only for cylinders 2,4,6).

Dealership write up says they swapped ignition coils and same misfire, OHM test injector- passed test. compression test-Cylinder 3 has intermittent compression, “Perform inspection of valves intermittent intake closure popping through intake manifold. POSABLE GUIDE OR VALVE SPRING PROBLEM. RECOMMEND CYLINDER HEAD. CUSTOMER ADVISED AND DECLINED”.

Now this is where it gets interesting- we drive the van for the two weeks we are in town between thanksgiving and Christmas, so we can decide over our holiday to either fix it and keep it or to replace the vehicle. We get in the van on Christmas Eve to drive to the airport, Christmas miracle- the van is running better AND the check engine light is off.

It’s now January 30, the van is still, seemingly, running fine and the check engine light has not come back on….it’s hard to believe this is really just a Christmas miracle…but what other explanation exists?! Just something wedged in their that cleaned itself out? Or something wedged in there now that isn’t being burnt out, but when it is we will have catastrophic issues…. Please tell me the theories!?

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