Hi, I have some questions and any replies would be appreciated. My jeep recently had a 04 engine put in and I really do need a tune up. So from my readings I see that champions are most popular I just want to confrim that. Is there a certain champion or whatever one they give me at Autozone. Next, should I replace all of the ignition coils since I am doing the sparkplugs or can I replace just one? My fiance noticed a small crack in one so I am not sure if one can be replaced or all. Also, when should these be replaced? the truck has 108,000 miles on it and it always seems to run kinda rough and has an annoying tick to it that drives me nuts. Any help would be appreciated.
There is probably a tag under the hood that tells you what plug to use, if not call your local dealer and they can tell you or Autozone can tell you when you pick them up. The ticking is not from sparkplugs though, you could have a exhaust leak, lifter noise ect... It's possible to put some rvt glue on the crack in the coil but if you can afford it I would just change it for a new one. The running rough could be other things too like sparkplug wires, rotor and cap, dirty throttle body ect... you might want to have a mechanic look at it so your not just throwing parts at it. I hear Jegs has a complete tune up kit that it probably wouldn't hurt to do anyway for around $100.
My 4.7 just got E3 plugs, and it LOVES them, $6.99 apiece though. Horsepower TV did a test with them and they got more horsepower using less fuel. This may be on the E3 website or the Horsepower TV website.
Did you get the 4.7 of 4.7HO. I think all Overlands have the 4.7HO. This is from wjjeeps.com:
4.7 Plug: Mopar® P/N SPRC12MCC4 Gap: 0.040
CAUTION: The standard 4.7L engine uses copper core ground electrode spark plugs, they must be replaced with the same type/number spark plug as the original. If another spark plug is substituted, pre-ignition will result.
4.7 HO Plug: Mopar® P/N SPRC7PYCB4* Gap: 0.040
CAUTION: Never substitute the original platinum tipped HO spark plug with a different part number. Serious engine damage may result.. HO plugs cannot be cleaned, damage to the platinum rivet will result. Also, do not use a wire-type gapping tool for the same reason. Use a tapered-type gauge. To prevent possible pre-ignition and/or mechanical engine damage, the correct type/heat range/number spark plug must be used.
*NOTE on 4.7 HO plugs: Champion RC7PYCB4 (p/n 3340) is the same as Mopar SPRC7PYCB4 and can be purchased for a fraction of the cost that Mopar charges.
i'm confused......why do you have a 2003 XJ Cherokee? Do you mean a 2003 WJ Grand Cherokee? Also look into the NGK plugs. I think they are around the same price as the E3's crashcraddock suggested. I'd suggest investing in some good wires like NGK or Bosch, etc. They will resist more frequency. In cheap wires the radio waves from other electrical components such as the radio can interfere with the wires causing hesitation, missfire, etc.
That plug is made by Champion and and has the Champion designation RC12MCC4. That's the plug to use. Also buy only a single coil to replace the one with the crack; on a 4.7, replacing coils is not a routine maintenance procedure.
I can't remember the number now but they were champion's and it was the number that I got from the dealer. He finally got the idle to normal but we found a vaccum leak. The only thing is i am not sure how to describe to you where that leak is. Its at the top closer to drive side. He put some starter fluid on it and it sucked it right in. Any clue what I mean without me know the actual name for it.