The Autolite XP985 still the Iridium plug of choice?
I wouldn't use those Bosch plugs in a TJ engine. The best choices are the factory specified NGK ZFR5N plugs or if you only want to change plugs every 60,000 miles rather than every 30,000 miles you can spend approximately twice as much and go with double platinum plugs such as Autolite APP985 or Champion 7034.
Personally, I don't see much point in spending the extra money for double platinum plugs. They do not provide measurable performance benefits over the specified NGK ZFR5N plugs and since I typically pull the plugs to check their condition at 30,000 mile intervals anyway (every 3-4 years based on my jeep usage) I might as well install fresh plugs while I'm at it.
Either of those gapped to .040 would be fine for your newer TJ. The iridium XP-985 will just outlast the APP-985 by about 100k miles to get no less than 200k miles or wear.Greetings all, hope everyone is doing well....working through a new to me TJ. It has been sitting awhile, like 700 miles in the last year, until I acquired last week...she is not happy right now and I have to resolve that!!
APP985 or XP 985? I see recommendations for both? Thanks in advance!!! (gapped to .040 right Jerry?)
2005 Rubicon
crap. I used the ramped one...Either of those gapped to .040 would be fine for your newer TJ. The iridium XP-985 will just outlast the APP-985 by about 100k miles to get no less than 200k miles or wear.
Make sure to not use a tapered style spark plug gapping tool on iridium or platinum plugs, they'll damage the coating. Use the type with the gapping tool that bends the electrode, like this one has on the left-hand side.
View attachment 223618
Just added the xp 985 to my amazon cart for $6.38. Will be tackling these after I take it to the shop and have the rear main seal replaced. Thanks again for all the helpful information on this site!Either of those gapped to .040 would be fine for your newer TJ. The iridium XP-985 will just outlast the APP-985 by about 100k miles to get no less than 200k miles or wear.
Make sure to not use a tapered style spark plug gapping tool on iridium or platinum plugs, they'll damage the coating. Use the type with the gapping tool that bends the electrode, like this one has on the left-hand side.
So got the plugs replaced this evening. They were also the XP, but the gaps seemed all over the place. Some were.040 some were .035, two were .025. Look pretty lean? View attachment 224156 I guess we'll see when I get the rest of the work done, waiting on a ODPA. Question though, is it necessary to use anti-seize on the coil bar bolts? Thanks!!Either of those gapped to .040 would be fine for your newer TJ. The iridium XP-985 will just outlast the APP-985 by about 100k miles to get no less than 200k miles or wear.
Make sure to not use a tapered style spark plug gapping tool on iridium or platinum plugs, they'll damage the coating. Use the type with the gapping tool that bends the electrode, like this one has on the left-hand side.
View attachment 223618
Look pretty lean? Im also tracking down elevated RPM when clutch is engaged when driving, it also had a run-on high idle the other day...ODPA going in, cant find a mopar sensor (discontinued), so its gonna be a Echlin. Going to clean the TB and idle control, maybe replace the O2s......hopefully these will solve it...Jeep was sitting for a long time...Lots of work to do stillNo antiseize needed for the coil rail bolts. If by that you're planning to put antiseize on the plug threads, use the smallest amount possible and make sure none can make its way to the electrode. Antiseize is conductive.