What spark plugs should I run in my 67,000 mile 2000 XJ? Haynes manual says Champion RC12LYC, another Forum member said Autolite APP-985 and the ones I pulled from the motor are Champion RC12ECC

 

I would say stick with the champions or go autolites. Those engines don't gain from having NGKs in them and usually run better on the champions.

TylerL. 94 ZJ 3" lift. My DD.

 

Whatever you choose, the argument on plugs will never end, but between the two champions the correct # for 99-01 is rc12ecc, not sure why but there are some differences between the plugs...You can check that out here http://www.championsparkplugs.com/sp...nufacturerID=2

Personally I'm running the champions.

 

on my old '98 i did a tune-up with autolites after maybe 3k miles i was starting to get a slight lopey idle only noticeable on a vacuum gauge and was getting spark knock...pulled the autolites and they were the culprits threw some oem champions ran so much better

 

i just did a tune up 2 weeks ago and the plugs i put in were Bosch Platinum +4. i think it runs great, and i didnt have to worry about the gap because you dont gap them, but they were kinda expensive, like $5 a piece

 

I pulled these out for the stock flavor champs, to be honest I didn't see a difference between them when I first put the 4s in or out, besides the normal gains from having new plugs, not worth the extra cash IMHO.

The 4s were also considerably shorter from top tip to the bottom prongs, I just thought that was odd when comparing them together.

Each to their own, I just wanted to toss my experience with them up!

 

Thanks for the info. Went to Napa and they showed Autolite APP-985... so I went with them.