Jeep Wrangler Forum banner
  • Hey everyone! Enter your ride HERE to be a part of JUNE's Ride of the Month Challenge!

1 - 7 of 7 Posts

·
Registered
Joined
·
494 Posts
Discussion Starter · #1 ·
Getting ready to do a tune up and have been watching the spark plug threads recently. Should the boots be replaced as well as the plugs or do they usually last okay? Any way to tell if they are good/bad or just replace as needed?
 

·
Knows a couple things...
Joined
·
49,389 Posts
Ok those boots are part of the coil pack, I wouldn't worry about them at all. Know that 4.0L engines with the coil pack are pretty fussy about what spark plug technology they like to run well on. Avoid ANY single-tipped platinum plugs like the Autolite AP985 or Champion 3034.

Two good performing plugs for your particular that will last something like 100k miles include the Autolite APP985 and Champion 7034. Those are both double-tipped platinum (platinum on both sides of the gap) plugs. A very good iridium tipped plug that will likely perfom well for 200k miles is the Autolite XP985.
 

·
Registered
Joined
·
494 Posts
Discussion Starter · #5 ·
Thanks Jerry. I wasn't sure how long the boots lasted or if they were recommended to replace after XXX miles, but noticed no one seemed to mention they were replacing them either.

Got my APP985 today. Bonus is Advance Auto has a $2 mail in rebate per plug now through 8/31/13. :dance:
 

·
Registered
Joined
·
494 Posts
Discussion Starter · #6 ·
Thanks Jerry. I wasn't sure how long the boots lasted or if they were recommended to replace after XXX miles, but noticed no one seemed to mention they were replacing them either.

Got my APP985 today. Bonus is Advance Auto has a $2 mail in rebate per plug now through 8/31/13. :dance:
ETA: actually sale through 7/31/13. Submission through 8/31/13 in case anyone else saw this sale and wanted to take advantage of it.
 

·
Registered
Joined
·
494 Posts
Discussion Starter · #7 ·
Okay, popped out the old ones today and replaced. NGK zfr5n were in, as spec on label along w Champion as choices. Don't know how old they are as they would be from previous owner and maintenance records were online at a dealership but don't say what was done when. Is that just a basic plug? I tried to look online but didn't find a lot about it as far as specs/materials to compare with the APP985 for performance.

They were worn. Gaps were worn to .65 in all cylinders except for #4 and #5 which were .55. Any idea what would cause the difference in gap wear? Anything I need to keep an eye out for?
 
1 - 7 of 7 Posts
Top