[bobsyeruncle]

My wife's 2015 FWD Platinum came home with the temp gauge pegged all the way on H and smelling of burnt coolant. Took it to the dealer and they diagnosed it with codes P0300 (overheating), P1217 (cylinder misfiring) and P17F1 (CVT judder). They re-clamped a hose to eliminate the leak, but now the car's ride is choppy because of the cylinder misfiring.

The car has 100K miles and this is the first time the check engine light went on and threw these codes. Would overheating cause a cylinder to mis-fire? The dealer said the cylinder mis-firing can be remedied through a "tune-up", which is just replacing all sparkplugs, nothing more. Am I missing something here?

What about the CVT judder? Since this is the first time I heard the car had problem with this, I was thinking the error was stored and the dealer happened to pull it up during the diagnostics.

 

[Pilgrim]

The codes should tell you which cylinder is misfiring. Check the work order for the code.

If the miss is on the front (accessible) bank, move the coil on the offending cylinder to another cylinder. If the miss moves with the coil, then the coil is bad. If not, it's the plug.

Your car is due for spark plugs anyway, so you need to do that. The difference is whether you should replace coils. It's a significant labor bill to reach the bank of cylinders next to the firewall, so if you replace coils you should do it with the spark plugs.

I would not have a dealer do this, especially if you need coils. I'd have an indy shop do it and save around 25% on the bill. "It's not rocket surgery."

 

[bobsyeruncle]

Thanks for the insight. As general practice, is it advisable to replace coils as well together with sparkplugs? How long do coils usually last?

 

[Pilgrim]

I don't subscribe to the theory that "when one goes, the others will too."

However, I also am a do it yourselfer. Getting at those rear cylinders is a genuine pain. If I was not a home mechanic I'd replace all of them with the plugs.

 

[MKUltra]

I agree with Pilgrims assessment, but I do subscribe to the "replace it while youre in there" thought process, as your mileage dictates a major service at this point or close enough to. The overheating of the engine PROBABLY tripped up the CVT as well, though SHOULD be okay... Engines and transmissions generate heat, and at their most efficient, the cooling has to be. In your case the heat rose with very little if any cooling so you can see the by product of taking it into a "extreme"

Id say get the oil, trans fluid changed and test the coolant after that overheat [as well as coils] Give her a little love and hopefully she keeps the reliability you want.