Got my Jeep in November, at 75 k I believe it still had the original plugs in it, Champion 2412.
I February I finally got around to pulling them gap was over 0.06.
I had read that Champions or Autolite AP were the way to go but they didn't have them locally. Decided to try the Bosch Platinum 4's.
I installed them and noticed that I had power back in the low rpm range. Great, the guys on the forum are wrong They were in for 6 weeks and about 1000 miles, noticed that idle wasn't quite right and it took a bit longer to start up. Pulled the plugs and found massive Carbon build up.
Needless to say I have ordered the Autolite AP's from Napa.
So you got over 70,000 miles with the stock plugs, but for whatever reason you went with something else to replace them? Why? I'd use the same thing that worked for me the first time. Autolite APs (whatever those are) may work, but why take the chance instead of going back with the others?
"The Wicked Flee When No Man Pursueth, But The Righteous Are Bold As A Lion."
Jerry has stated many times the the Champion Truck plugs are very good but he prefers the Autolite AP985 for their added longevity, this is for TJ's with Distributer, for Coil Packs I believe it is the double platinums APP 985 that are needed.
Friends don't let Friends run Bosch
Got my Jeep in November, at 75 k I believe it still had the original plugs in it, Champion 2412. .... They were in for 6 weeks and about 1000 miles, noticed that idle wasn't quite right and it took a bit longer to start up. Pulled the plugs and found massive Carbon build up. ....
They look like the engine is running really rich .. maybe you have other issues.
[I]Who's[/I] in front ?
I had the bosch platinum 2s in my Jeep when I bought it. The Jeep would just die at idle. It would start right back up, but it started to get worse. I was troubleshooting EFI, when I got good advice here in JF to start with the basics. So I did a tune up with regular champion plugs and the problem went away. Runs like a champ now. I have a 4.0 with the coil packs.
With all this plug talk I changed mine too, these had, I would guess, 59K as they were in when I bought the rig, Champion RC12LYC and was running fine but looks like they were due. Put in a fresh set of Autolites and the pick up seems to have improved.
'97 Black TJ - 4 banger - 5 speed
Proud user of the "K.I.S.S." Principle.
Black Jeep Society #264