2013 Grand Touring Cylinder 2 Misfire/Corroded Plug

My 2013 CX-5 Grand Touring AWD with 150,000 miles had misfire issues last year. I replaced the spark plugs with Denso TTs and took it to the dealer and they cleaned the intake/places I could never get to and replaced the fuel injectors. This solved the problem up until about a month ago it started to do the same thing where during any random moment of acceleration the tire pressure, check engine, and traction light all suddenly flash on and the car loses power and slows down to about 20 mph. The codes are reading P0302 cylinder 2 misfire & P013A 02 sensor slow response - rich to lean bank 1 sensor 2. I replaced the coils and the plugs; however, when I took out the old ones they had dark burnt rings on the lower portion of the ceramic and the middle/left plug (if you are looking at the car from the front) was corroded on the tip while the other 3 were normal. After seeing the code I am assuming I need to replace the 02 sensor, but the corroded spark plug has me concerned there could be problems elsewhere. Also, I syphoned some gas from the tank and it didn't seem to have any dirt particles or water in it.

Any ideas on what could be going wrong? I don't trust the dealer, the last time it was there they were dishonest and I know they will just recommend the expensive cleaning service again without really looking at the problem. I thought I once read something about these models having issues with water in the gas, or could it just be the bad sensor or a bad catalytic converter? The car still seems to run great in the moments between those slow-downs and I definitely felt I big improvement in performance with the new plugs and coils.

Thanks in advance!

150k miles is a bit of a stretch for original shark plugs. Have you hit a speed bump by your exhaust at some point? Has engine noise become louder? Exhaust gasket before the catalytic converter should be checked, that's potential cause for P013A.
Corroded plug might have been the cause of misfire. Check the coil boot for corrosion too.

You may be going into limp mode with a transmission problem. Look at the transmission problem threads and the dash lights they get...

There is a ion feedback system from the spark plugs,
make sure your plugs support this, you may need to put in Mazda plugs to make sure this is not the problem... Here is some of the theory
http://bmwmotorcycletech.info/ioniza...-susbystem.pdf
and http://nema.club/2014wsm/service h...0g0004400.html and
http://www.mcx5.org/spark_plug_inspe...2_0_-1154.html

Any luck with figuring out what the cause was? My 2013 CX-5 Sport with 160,000 miles is going through the EXACT same thing

I was going to say perhaps the spark plugs were not the exact right resistance and to try OEM plugs.
Wow this post is 3 years old!

It ended up being a combination of bad ignition coils (I had the Mitsubishi ones they recommend replacing) and a low voltage battery although I did replace the spark plugs while I replaced the coils so that probably helped

kstlz said:

It ended up being a combination of bad ignition coils (I had the Mitsubishi ones they recommend replacing) and a low voltage battery although I did replace the spark plugs while I replaced the coils so that probably helped

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Thanks for the update. How many miles have been on your reused spark plugs?