I want to replace my plugs which have 180000 on them. I bought car brand new. I pulled out denso iridium sk j20dr-m13 (3401) but on Honda site says it takes sk j20dr-m11. I have call different auto parts stores and some say the m-13 is for dx or ex only not the lx. But those were the ones I pulled out. Other people say it doesn't matter. I got 180 out of wrong plugs ! Don't know why they put wrong ones in factory, maybe that's all they had. Should I put them back in or the m-11 which all Honda sites have in parts list that would fit my lx . Thank you

 

I think the last numbers are just the gap.
11 is 1.1mm = 0.043"
13 is 1.3mm = 0.051"

Curious because I didn't think the LX & EX engines are different?

But from Majestic Honda, it's the California-spec engine that takes the m13 plug regardless of LX or EX.

 

So which one would you put in ? The one that came out of it ? The one that on some parts sites that says does not fit , being the 13 or the one that is listed on majestic site m-11

 

If I read your original post correctly, you got 180,000 miles out of the factory plugs; I say don't mess with success, use the same plugs.

 

Yeah, don't mess with success.

Either one will FIT. I've had more times than I can remember when parts-sites get the details wrong, and this time it's simply the same sparkplug with a different gap.

Maybe you have the California-spec car. They get traded around between dealers, and they don't all end up in California.

 

Can I check vin on car to tell if California car and the 13 are correct

 

Denso SKJ20DR-M13 are the recommended spark plugs for LX-SULEV, EX-SULEV, and EX-L-SULEV.

Some LX, EX, and EX-L are PZEV vehicles, which are SULEV-rated and have zero evaporative emissions. Available on select LX and EX-4 cylinder models with AT in CA and some Northeastern states.

http://news.honda.com/newsandviews/article.aspx?id=2003091751149

Your car is probably an LX-SULEV from a Northeastern state.

You can enter your VIN at an online Honda dealer site like Bernardi Honda Parts, etc.

 

There's also a VIN decoder that Angelo linked in a sticky at the top of the forum.

 

So I plugged in vin and doesn't say car is sulev-rated vin JHMCM563X4C017732

 

Look at the emission sticker in the engine compartment, it should say PZEV or S-ULEV.