2013~2016 CX-5 Spark Plug Issue

[AVSJay]

I have a 2016.5 Mazda cx-5 grand touring. I replaced my spark plugs last week and all went smooth. Car started up, idle fine, no lights. I drove it for 2 days than randomly started the car and saw the orange check engine light on. Car also idled rough when at a light.

I got home and after a little, took out the spark plugs to see if something happened but they looked ok.

My issue now is the first 2 spark plugs (from right to left), screw in about 2 turns by hand and just get stuck. No wrench or anything I did was able to get them to install again. The 3rd and 4th were fine and when I put the good ones into the one getting stuck, the good one as stuck also. When putting the one that wouldn’t spin into the first, it went fine into the others so I’m thinking the threads are f’d.

I think I over tightened them and when removing I messed it up more somehow. I’m at the point where I don’t know what to do as I can’t get car anywhere and there’s so much info that I don’t know where to begin.

I’m hoping there’s something I can do to allow the plugs to spin by hand but both spark plug 1 and 2 spin twice and just stop. If I try to use socket wrench I can tell there not going in perfectly straight I don’t think.

I originally used new one and even bought a second set but same thing. Spark plug hole 1 and 2 have same issue, 3 and 4 are fine.

I’m not great with cars but seemed straight forward… which now really messed me up trying to get to work and figure out what to do.

Any help would be really appreciated. Are there any pictures I could attached that would help someone diagnosis I have a bunch. I just don’t really know what to look for.

 

[Mazdiod2]

You might try a thread chaser. It's a threaded item with a chunk cut out of one side of it that cleans the threads as you screw it in. Also look down in the holes with a good flashlight maybe you can see what's wrong.

 

[AVSJay]

You might try a thread chaser. It's a threaded item with a chunk cut out of one side of it that cleans the threads as you screw it in. Also look down in the holes with a good flashlight maybe you can see what's wrong.

Nothing looks wrong or different (like I said I’m not a car guy, but I don’t see any noticeable difference between the working ones and non-working.

My only thought is the threads you screw the spark plug into itself are maybe dirty or have some shavings in it. Do you think a back tap tool would work?

Also for the thread chaser, do you know a good one for Mazda’s? I need one that’s like 10” or longer I’d imagine.

Thanks for replying!