2013 CX-5 P0302 Cylinder 2 Misfire issue

[mhj]

Hello all,

I have a CX5 sport with about 130,000 miles on it. I have been dealing with a cylinder two misfire for quite some time. I replace the spark plugs twice. I’ve also replaced all the coils. I also cleaned out the intake valves. I took it to a mechanic who was not very helpful. The car would lose power, but improves after replacing spark plugs only to come back a few months later. Has anybody experienced this? Any thoughts or ideas? I have not done a compression test or replace the fuel injector. Thanks.

 

[Jmaz]

What do the plugs look like after pulling them out? Is #2 plug fouled compared to the others and it might take a few months for it to foul and misfire. Do you disconnect the electrical connector to the coils before removing them. If #2 connector has corrosion issues, removing and reinstalling a connector can break a corrosion "seal" that restores good contact only for it to corrode again after a period of time and again cause a poor electrical connection.
Does the loss of power happen gradually or is it just concurrent with the misfiring.

 

[mhj]

Spark plug didn’t look much different than any other ones. The loss of power seems to happen a few months after installing new plugs. Car would be driving fine and then lose power with the gas pedal not responding and check engine light flashing. I turn the car off. Start it back up and its fine.

 

[HyFlyer]

Spark plug didn’t look much different than any other ones ...

Okay, let's talk about the spark plugs ... What brand / model and where are you getting them? What is the resistance of the plugs when new and when you pull them out after a couple months and they have problems?

There are reports of counterfeit plugs out there in the world that are junk.

 

[mhj]

I got them from Rock Auto which has yet to let me down. I have not checked their resistance. NGK 92274 LKAR7AHX-S Ruthenium

 

[Kedis82ZE8]

I wonder if there is something up with the #2 fuel injector?

 

[mhj]

Should I just replace it or worth trying to clean it out?

 

[Mazdiod2]

If you havent tried a bottle of some kind of fuel injector cleaner it's worth a try. The kind that contains Techron is supposed to work.

 

[mhj]

Yep. I threw some of the CRC stuff in there. I’ll try Techron to for the heck of it

 

[madar]

Techron is very good stuff. I've used it to clear up misfire issues on other cars. That's the first thing I would've tried.

 

[mhj]

Sounds like a good simple idea. I wish I had thought of that! I’ll try the injector cleaner

 

[yrwei52]

I got them from Rock Auto which has yet to let me down. I have not checked their resistance. NGK 92274 LKAR7AHX-S Ruthenium

The NGK equivalent for OEM PE5R-18-110 spark plug Mazda specified for your 2.0L is NGK Laser Iridium spark plug ILKAR7L11 / 94124.

You should always use OEM plugs or at least the NGK equivalent. Don’t use anything else. Some even questioning the legitimacy of NGK plugs from RockAuto.

Multiple Misfires without an engine light!

Spark plug dilemma (2014 CX-5)

 

[mhj]

No kidding! I went with the Ruthenium thinking it would be better! I’ll order another set just to be safe. Thanks

 

[Mazdiod2]

If you continue to have problems I would start to suspect a problem with the cylinder. You mentioned you haven't had the compression checked which at 130K miles might be a good idea. If you have something wrong you might be fouling whatever plugs you install.

 

[mhj]

If you continue to have problems I would start to suspect a problem with the cylinder. You mentioned you haven't had the compression checked which at 130K miles might be a good idea. If you have something wrong you might be fouling whatever plugs you install.

Would it only affect one cylinder? Come to think of it, I did replace the spark plugs at one point with the NGK 94124 with the same issue returning

 

[mhj]

The other issue is the car runs fine for a bit even with the misfire and after a few months it starts to go limp.

 

[yrwei52]

The other issue is the car runs fine for a bit even with the misfire and after a few months it starts to go limp.

So each time the car goes into the limp mode after few weeks you did something, and the DTC code stored would always be “P0302 Cylinder 2 Misfire”?

What kind of ignition coil pack do you have right now? You can swap around the spark plugs and coil packs and see if the misfire moves to different cylinder? If not, compression test、leak down test like @Mazdiod2 suggested should be considered.

​

 

[mhj]

Yep. Everytime same code. Right now car is driving fine with the engine light and same code. I tried the swaps for coils and plugs. Nothing. Nothing different when I unplug the wires with the engine running on cylinder 2 compared to the rest of them either. Deplhi gn 10625 are the coils.

 

[Mazdiod2]

Yep. Everytime same code. Right now car is driving fine with the engine light and same code. I tried the swaps for coils and plugs. Nothing. Nothing different when I unplug the wires with the engine running on cylinder 2 compared to the rest of them either. Deplhi gn 10625 are the coils.

So it's a very intermittant problem? If you clear the codes how long to return?

 

[Kedis82ZE8]

Looks like compression should be around --->

885 {9.02, 128} [300] / (kPa {kgf/cm2, psi} [rpm])

2.5L on 14-16.5 at least goes up to this --->

954 {9.73, 138}[300]