2013 jeep grand cherokee 3.6 spark plug replacement

Hi, I decided to change my plugs in my 2011 wk2 with 85K miles. It ran ok but idle was rough. Much to my surprise, this was harder than I thought; took me almost 5 hours. Here are the steps I took and some things that I experienced.

I bought OE champion plugs, Thread anti-seize, die-electric for plugs wires and electrical connectors and intake manifold gaskets.

I removed the engine cover, intake hose with air box cover and disconnected the air sensor.

The first 3 plugs on passenger side are in plain view. Took 20 minutes to change these. unscrew coil, pull straight up. 5/8 socket. Torque to 13 ft lbs. Done!

The remaining time was spent on the drivers side. You have to remove the intake manifold. No easy task!

First I disconnected the electrical connections to the throttle body, then I disconnected the vacuum hose behind the throttle body. There are two nuts that need to come out on the bracket behind the throttle body.

Then there are 7 screws that hold the intake manifold. The one near the firewall is difficult. Then you need to remove the two nuts on the drivers side of the intake manifold and since these are posts, you have to remove the two nuts that hold these brackets on. Loosen just enough to pull the bracket back off the posts. Again, the lower nut on the bracket near the firewall took the most time. There is also a clip that holds the AC hardline which needs to come off. I pryed it off with a screwdriver. not easy! then taking that nut off in that very tight space was not fun! This was the worst part of the job.

Once everything is loose, the manifold can come off.

Couple of tips: Ensure you take the screws completely out of the manifold. Otherwise they will drop down and prevent the manifold from sliding out. You don't need to remove the hose at the back of the manifold, there is enough slack to move it over. There are a couple of wire ties you have to cut. The one holding the hose at the driver's side corner of the intake manifold and the electrical harness going to the throttle body.

I also ordered new intake manifold gaskets since they were easy to replace.

With 85K miles, these plugs were worn pretty badly. No way they could go another 10K miles without degrading performance. There are a few youtube video's of a guy changing his plugs on a charger- same engine. There are slight difference which I have outline here.

Good luck! (sorry, I did not take any pictures)

That sounds like a much bigger job than I was expecting. Now that you've done your first, how long do you think the next one will take?

probably 2 hours less time now that I know some tricks. Again, I spent most of the time on that back bracket nut on the drivers side. just not a lot of room to get in there. Not sure why they didn't use another nut rather than the press on ring to hold the hard line on.

My hat's off to you. I know a lot of guys like to do the maintenance on their vehicles themselves. I spent decades doing it myself. These days, as long as there's food in my freezer, I'm willing to pay someone to put up with the aggravation.

My hat's off to you. I know a lot of guys like to do the maintenance on their vehicles themselves. I spent decades doing it myself. These days, as long as there's food in my freezer, I'm willing to pay someone to put up with the aggravation.

I'm the same way. At 63 my "do it yourself" career is quickly coming to a close. I just don't have the patience level any more. I always used to change the plugs on my F-150 because it was quite easy. I also bought new wires, rotor, and distributor cap at the same time so I wouldn't have to be careful removing the old ones. But now I'm done doing that as well. It's just so much easier to pay someone.

probably 2 hours less time now that I know some tricks. Again, I spent most of the time on that back bracket nut on the drivers side. just not a lot of room to get in there. Not sure why they didn't use another nut rather than the press on ring to hold the hard line on.

A gearwrench/ratchet wrench works best for the driver side brackets. No need to remove the lower bolts that secure the bracket to the engine itself. Another trick is to use a inverted torx socket and remove the entire stud that goes through the top portion of the bracket to the intake plenum. It will push the brackets back enough to lift the intake right out. During reinstall, there is really no reason to use the bolts on the studs. Install the stud through the bracket first and then thread it into the intake plenum. The studs have a flange that will secure the intake plenum to the brackets pretty much painlessly.

For that rear most bolt closest to the firewall, a 1/4" rachet and appx a 3.5" entension and you can get right to it. If you have a 10mm universal socket ( not a universal swivel) and a medium extension, it's even easier.

Ratchet, Thanks for the reply and tool recommendations. I will try to find on Amazon. Always makes the job easier when you have the right tools.

Ratchet, Thanks for the reply and tool recommendations. I will try to find on Amazon. Always makes the job easier when you have the right tools.

No prob. I've been meaning to put together a how to on that but simply haven't had the time or be near my camera to do so.

I did mine today. There are write-ups in other forums that are good advice. Good idea in the OP here about ordering the intake manifold gaskets.

Some issues to watch for:

I found that removing the throttle body gave me room to get at the passenger side bracket.

The 7 bolts that compress the gaskets, they are designed to stay in the upper manifold once fully unthreaded out of the lower. This is important, because if you try and pull them out they may not function as well in this manner. The three that are hidden are basically impossible to pull out anyway, so leave them in, fully raised off the lower manifold.

Then there's the three brackets that hold the manifold down in place. Not sure why these are there. Easy to remove the nuts, but only the two brackets on the drivers side can be loosened. The one on the passenger side behind the throttle body can't be- it' a large bracket, looks big enough to support the engine on a hoist.

So the trick is to raise the inner 7 bolts, remove the three bracket nuts, loosen the drivers side brackets, then slide the manifold toward the drivers side. Before you can take it out you'll have to remove the PCV hose on the back.

While you have this off, good idea to replace the PCV valve, as it's also a 100k mile service.

I saw a write-up that said four hours. I said "Yeah right." It took me almost exactly four hours.

I attempted mine several weeks ago. The passenger side are fairly easy. Getting the upper intake manifold off to get to the ones on the driver's side was too much of a hassle. I took it to the dealer for those, but if I had to do it myself, I would cut slots in the tops of the support brackets on the drivers side so that the brackets did not have to be loosened. This would also facilitate other repairs where the upper intake manifold needed removal. I still might cut those brackets if a future repair requires it. Definitely an engineering oversight.

My hat's off to you. I know a lot of guys like to do the maintenance on their vehicles themselves. I spent decades doing it myself. These days, as long as there's food in my freezer, I'm willing to pay someone to put up with the aggravation.

I hear ya, Looking at changing mine and the time it would take me is worthpaying someone to do it

A gearwrench/ratchet wrench works best for the driver side brackets. No need to remove the lower bolts that secure the bracket to the engine itself. Another trick is to use a inverted torx socket and remove the entire stud that goes through the top portion of the bracket to the intake plenum. It will push the brackets back enough to lift the intake right out. During reinstall, there is really no reason to use the bolts on the studs. Install the stud through the bracket first and then thread it into the intake plenum. The studs have a flange that will secure the intake plenum to the brackets pretty much painlessly.

For that rear most bolt closest to the firewall, a 1/4" rachet and appx a 3.5" entension and you can get right to it. If you have a 10mm universal socket ( not a universal swivel) and a medium extension, it's even easier.

Hi I have a question on your post. I just tried to change mine and I had no luck with the drivers side plugs because of those brackets. Can you explain how I get that upper manifold off. i was going after the back bracket near the firewall on the passengers side. The I tried the brackets on the drivers side but I couldn't get off the nut that holds the back bracket on. So your saying I don't have to loosen the back bracket at all?

Hi I have a question on your post. I just tried to change mine and I had no luck with the drivers side plugs because of those brackets. Can you explain how I get that upper manifold off. i was going after the back bracket near the firewall on the passengers side. The I tried the brackets on the drivers side but I couldn't get off the nut that holds the back bracket on. So your saying I don't have to loosen the back bracket at all?

There should be a 10 mm nut on the rearward passenger side bracket where it attaches near the top of the intake manifold near the throttle body. For both of the driver side brackets, on the TOP studs, use an inverted torx bit (I think it's an E8) and screw the entire stud out from the intake manifold. This will push the brackets away from the manifold You won't have to touch the bolts on the bottom of the brackets. When you go back together, install the stud through the front side of the brackets and upon tightening, it will pull the bracket back onto the intake manifold.

There should be a 10 mm nut on the rearward passenger side bracket where it attaches near the top of the intake manifold near the throttle body. For both of the driver side brackets, on the TOP studs, use an inverted torx bit (I think it's an E8) and screw the entire stud out from the intake manifold. This will push the brackets away from the manifold You won't have to touch the bolts on the bottom of the brackets. When you go back together, install the stud through the front side of the brackets and upon tightening, it will pull the bracket back onto the intake manifold.

Wow, no shit lol. I wish I read your post the past weekend. 5 hours and only 3 plugs changed. Now this should take no time. Just to make sure I'm understanding. I will take the two 10mm nuts off the bracket on the passenger side. Then just unscrew the studs from the manifold on the drivers side and the brackets should back off enough to pull the manifold off without having to touch the nuts on the bottom of the bracket. Correct?

Thank you so much I was going to have a go at the brackets again this weekend because I refuse to pay $600 at the dealership to have spark plugs changed. I am no longer dreading Friday afternoon.

Wow, no shit lol. I wish I read your post the past weekend. 5 hours and only 3 plugs changed. Now this should take no time. Just to make sure I'm understanding. I will take the two 10mm nuts off the bracket on the passenger side. Then just unscrew the studs from the manifold on the drivers side and the brackets should back off enough to pull the manifold off without having to touch the nuts on the bottom of the bracket. Correct?

Thank you so much I was going to have a go at the brackets again this weekend because I refuse to pay $600 at the dealership to have spark plugs changed. I am no longer dreading Friday afternoon.

Yes. Remove the nuts, then the studs. I've seen a few of these engine that has 13mm nuts on the brackets FYI. Don't touch the bolts on the bottom of the brackets. Same with the upper stud one near the throttle body. They are reverse/inverted torx. Make certain you have ALL of the bolts removed from the top of the intake plenum. There is a sneaky one near the middle. When reinstalling the studs for the brackets, don't use an impact or a lot of muscle. A 1/4 drive hand ratchet will be just fine. Remember, you're screwing into fantastic plastic.

Shoot me a PM if you have any issues.

Yes. Remove the nuts, then the studs. I've seen a few of these engine that has 13mm nuts on the brackets FYI. Don't touch the bolts on the bottom of the brackets. Same with the upper stud one near the throttle body. They are reverse/inverted torx. Make certain you have ALL of the bolts removed from the top of the intake plenum. There is a sneaky one near the middle. When reinstalling the studs for the brackets, don't use an impact or a lot of muscle. A 1/4 drive hand ratchet will be just fine. Remember, you're screwing into fantastic plastic.

Shoot me a PM if you have any issues.

There are two nuts and studs on the bracket near the throttle body. Do I remove both studs? The one closer to the fire wall is a PITA to get to. Or is just removing the studs on the drivers side and just the nuts on the passenger side sufficient?

Sorry so many questions I just don't want to loose another 5 hours lol.

Thanks again.

There are two nuts and studs on the bracket near the throttle body. Do I remove both studs? The one closer to the fire wall is a PITA to get to. Or is just removing the studs on the drivers side and just the nuts on the passenger side sufficient?

Sorry so many questions I just don't want to loose another 5 hours lol.

Thanks again.

It's been a while since I've had one to work on honestly. If it has double brackets or single, just the top nuts/studs regardless. The back one closest to the firewall isn't hard if you have some 1/4" gear. Appx a 3" extension, swivel, and a short 10mm should get you there. I've had a few where I had to remove the throttle body for some extra wiggle room.

Took me no more than 2.5hrs but only after reading this post and checking out some YouTube videos. Got the inverted Torx but only used on the passenger side screw, that allowed me to lift up and then slide the manifold to the left (passenger side). Got the 6 gaskets on Amazon, they were blue.

probably 2 hours less time now that I know some tricks. Again, I spent most of the time on that back bracket nut on the drivers side. just not a lot of room to get in there. Not sure why they didn't use another nut rather than the press on ring to hold the hard line on.

Hey buddy I ran into the same problem with this nut on the bracket couldn't figure out how to get in there so I had to put ALL nmback together! Very upset. How did you take that off? What tools? Open ended wrench?