I have SCOURED the internet trying to find answers on how to replace these things. I have found nothing at all. I have also searched this forum and others. Does anyone have, in layman's terms, instructions on how to replace them. I have a 2009.
Careful pulling the wires off the plug. Mine were stuck on and ended up breaking two of the wires. After the first had to run to the store and buy a new set.
The 3 on the drivers side are cake, the other three however.... Well, let's just say after sitting on my engine block, getting the 3 others pulled out (2 of the 3 yanked out) then I had a fun time (4 auto parts stores) searching for a new spider in my mother in laws car, I finally got the new ones in. Also an 09. I definitely suggest a new set of wires before going forward.
I cant get that rubber boot off the plugs. Its pissing me off because I've done it on my old 4runner. I just can't get it done on this. All the videos I've came across were for everything besides my jeep.
There's a tool you can buy that grips the boot down near the plug so your not yanking on the end of the wire. The safest way is to buy a back up pair of wires just incase you break one.
They also must be gapped before being installed. Even if the were set at the factory, they have been bouncing around in the box. Take the time to agp them.
Any spark plugs I have bought have always come packaged with a small cardboard tube around the business end of the spark plug, extending out further than the end of the spark plug itself. This prevents the gap from being altered from bouncing around in the box.
Also, be aware that some types of spark plugs will likely get damaged if you attempt to adjust the gap.
+1 some dielectric grease, I usually smear bit in the boot opening.
For getting them off, try twisting the boot.. I've even used pliers to give it a quick twist. I've never broken a wire trying to get it off, but I haven't done these either.
I see a spark plug boot tool on my future, I'm pretty sure those 'hook' the boot at the bottom.. should be easy.
I changed my plugs and wires back in January when I had the battery tray pulled out to repair wires (dang squirrels). It was just so much easier to change the passenger side plugs with nothing in the way that I will just go ahead and remove all of that right off the bat when I do it again.
Replaced spark plugs on a few 3.8's. I'll share what I've learned.
Doing them 1 at a time prevents you from mixing up the wires.
Spark plug boot removal tool is helpful and should only cost about $8.
Dielectric grease in the plug boot will help next time. Also keeps water out. Copper anti seize on the plug threads also helps. Gap to factory spec as well.
After you remove the boot blow out the recess with compressed air before you remove the plug so you don't drop grit into your combustion chamber.
Can of keyboard cleaner with long nozzle will work if you don't have an air compressor.
Shine a light down the spark plug hole.
If it looks like chocolate cake inside there Mopar combustion chamber cleaner might be in order. Takes 2 cans. 1 split evenly for combustion chambers 1 for intake manifold. It will smoke a lot, this is normal as it burns off the build up carbon. Use you stock plugs during treatment, put the new ones in after. Changing your oil and PCV valve afterward is a good idea too.
If spark plugs feel seized don't force them. Spray some liquid wrench down there and let it sit for an hour. Then use a large socket wrench and tap the handle with a hammer to free the stuck plugs. Think gentle impact wrench.
Don't over torque the news ones, they don't need to be gorilla tight.
As others stated drivers side is fairly simple.
Passenger side you can do with a wobble/universal joint and an extension. Keep several lengths handy. Use a spark plug specific socket, it has a grommet that holds the plug in place for you. if you do drop a plug, re-gap it.
There are a few hoses and wires in the way, disconnect them first. Worst is the far back passenger plug next to the firewall.Take the battery out if your struggling. Just gives you a little more room to work with. If your Jeep is lifted a small step ladder helps. You gotta get elbows deep in there.
Some say remove the passenger tire and fender liner. I've never found it necessary.
Always start the threads slowly by hand so you can stop and start over before it cross threads and ruins your day.
I twist counterclockwise until I feel the threads click then go clockwise to start it.
I like to label the plugs as they come out so I can study them afterward for any indication of oil blow-by or lean condition in a specific cylinder.
Your Jeep should idle smoother, accelerate better and you might even pick up another mile or two per gallon.
Replaced spark plugs on a few 3.8's. I'll share what I've learned. Doing them 1 at a time prevents you from mixing up the wires. Spark plug boot removal tool is helpful and should only cost about $8. Dielectric grease in the plug boot will help next time. Also keeps water out. Copper anti seize on the plug threads also helps. Gap to factory spec as well. After you remove the boot blow out the recess with compressed air before you remove the plug so you don't drop grit into your combustion chamber. Can of keyboard cleaner with long nozzle will work if you don't have an air compressor. Shine a light down the spark plug hole. If it looks like chocolate cake inside there Mopar combustion chamber cleaner might be in order. Takes 2 cans. 1 split evenly for combustion chambers 1 for intake manifold. It will smoke a lot, this is normal as it burns off the build up carbon. Use you stock plugs during treatment, put the new ones in after. Changing your oil and PCV valve afterward is a good idea too. If spark plugs feel seized don't force them. Spray some liquid wrench down there and let it sit for an hour. Then use a large socket wrench and tap the handle with a hammer to free the stuck plugs. Think gentle impact wrench. Don't over torque the news ones, they don't need to be gorilla tight. As others stated drivers side is fairly simple. Passenger side you can do with a wobble/universal joint and an extension. Keep several lengths handy. Use a spark plug specific socket, it has a grommet that holds the plug in place for you. if you do drop a plug, re-gap it. There are a few hoses and wires in the way, disconnect them first. Worst is the far back passenger plug next to the firewall.Take the battery out if your struggling. Just gives you a little more room to work with. If your Jeep is lifted a small step ladder helps. You gotta get elbows deep in there. Some say remove the passenger tire and fender liner. I've never found it necessary. Always start the threads slowly by hand so you can stop and start over before it cross threads and ruins your day. I twist counterclockwise until I feel the threads click then go clockwise to start it. I like to label the plugs as they come out so I can study them afterward for any indication of oil blow-by or lean condition in a specific cylinder. Your Jeep should idle smoother, accelerate better and you might even pick up another mile or two per gallon. Good luck!
And.... don't believe that the plugs will last 100k. I took mine out at 90k and they were toast. I'd give those plugs 50k at most. Replace wires while you are at it.
I generally check at half their suggested life. 100k mile plugs at 50k, etc. So far it's worked out well.
Also, seconding doing one plug a time. I had a couple of wires swapped on a 327 and spent a day chasing my tail trying to figure out why the hell I had a backfire. I was positive I had them correct.
did that on a 4.0, it will actually run surprisingly well with 2 wires swapped
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