Ignition coil #3 misfire- 2013 sports awd 130k

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mazda cx5 13
So I went to grocery shopping yesterday and while coming back, it started vibrating and lost power. Check Engine light, TCS, and TPMS lights came on. Nearest mazda dealer is 50 miles away, so went to autozone and got the codes checked and they said, ignition coil #3 is misfiring and need a replacement. I ordered one with them and will get it changed sometime today.
It’s 2013 sports AWD at 130k miles.

Should I get only 1 or all 4 replaced? Any recommendation on where to buy? I saw medmazda has $90 a piece while autozone has one for 117 (Duralast - that’s the one I am getting right now), Amazon for even less. Is it common to have cylinder misfiring at this many miles? Should I get complete diagnostic at the dealer as well?
Also, which one is cylinder #3?
Thanks!
 
A misfire code at a particular cylinder # like yours can be caused by lots of issues.

I would first go ahead and disconnect coil#3 from the harness, inspect the connector carefully, making sure there is no issues with the connector pins being corroded, or wire issues.

If nothing obvious, I would then remove the coil, and then remove the spark plug to inspect the spark plug. Is it possible that the spark plugs have never been changed?

Cylinder #1 is the one closest to the fan belts, # 2,3,4 are sequential from there.

If you want to verify the problem is with the coil, you can swap the coil to a different cylinder, and see if the misfire follows the coil to the new cylinder.

If you indeed need a coil. I would stay with the original Mazda part for the coil. It is a high quality item.
 
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How do you know it's not the plug(s). I would have Mazda check it before purchasing coils especially cause they're not cheap.
If it's a coil I would only replace with OEM.

My previous Maxima had serious coil problems and a lot of people replaced with aftermarket to save a few bucks and ended up replacing again with OEMs after experiencing all the problems associated with crappy made coils.
 
I changed the spark plugs at around 80k. Auto zone ran the code through their system and it said ignition coil #3. Since the nearest Mazda dealer is 50-60 miles away, my cheapest option seems ti be get it drivable (by getting after market) so that i can at least reach the dealer and get the complete diagnostic.
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Update:

got it changed at auto zone and now its working perfectly fine. Check engine light, tpms and TCS are all off now.

About a week before ignition coil failed,i did notice that every time I turned off the engine I kept hearing fan sound from the engine for about 10 minutes after turning it off. That is also gone after coil replacement.

I will get it completely checked at a Mazda dealer the next time i go there.

Thanks mazdadude, paris1 and wlong01 for your help.
 
I changed the spark plugs at around 80k. Auto zone ran the code through their system and it said ignition coil #3. Since the nearest Mazda dealer is 50-60 miles away, my cheapest option seems ti be get it drivable (by getting after market) so that i can at least reach the dealer and get the complete diagnostic.
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Do you know what kind of spark plugs you used for replacement at 50K miles ago? If the replacement spark plugs were not OEM, they may prone to cause misfire. The maintenance interval for OEM spark plugs is 75K miles. In other words, if you're using after-market spark plugs they could also make your ignition coil failing.

Interestingly the report from AutoZone listed several causes for code "P0303", but only "Weak ignition system" indicates something related to ignition system which may be failing but it doesn't specifically say it's ignition coil. I wonder how did AutoZone figure out it's ignition coil? May be they have seen this problem many times before?
 
I am not exactly sure how they pinned it down to ignition coil but they were very sure about it.

The spark plug i bought was NGK 94124 ILKAR7L11 Laser Iridium Spark Plug from Amazon as suggested by many here that its the same as the one Mazda uses.


https://www.amazon.com/dp/ (commissions earned)


The other thing that puzzled me was the engine making fan/belt running sound for about 10 minutes after turning off the car (noticed about a couple of week before misfire happened) which also went away with ignition coil replacement.

As I know very little about cars, I did not think much of it at the time and thought I would get it checked when i visit the dealer the next time for oil change. But now looking back, that was definitely related and indication of something is about to go bad.

My plan is to get it completely diagnosed the next time I go to the dealer.
 
I replaced all 4 ignition coil and spark plugs when 1 failed. I dont want to be driving in the highway if another 1 fails. It s not a good feeling driving in the limp mode.
 
And yes, a coil going bad after that many miles is not unusual.

Yesterday, my cousin's 4-Runner at 120k miles had a gasket leaking oil unto one of his spark plugs. Just one of those things to inspect at 100K plus miles.

At 100k I'm going to start using my BlueTooth OBDII scanner thingy tool and Torque Pro app to check for codes.
 
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