How to change spark plugs on a 2012 DJ with V6 and question on rough idle

[2004CSOTP]

Hello all,

This is my first time posting on this forum. I have a 2012 DJ with the V6. It was at the dealer a few weeks ago for misfiring. They replaced an ignition coil on cylinder number 3 and recommended I replace the spark plugs, air filter, and flush the fuel system. I thought 100 bucks for an air filter and 500 to change spark plugs was too much so i just had them change the coil. When I got it back, I replaced the air filter myself (12 bucks) and ran fuel system cleaner through it. The misfire and low speed shaking were gone, but now the shaking is back. I'm going to change the spark plugs, but I'm not convinced that's the cause of the shaking.

First, I can't seem to find information on how to remove the intake manifold to get at the spark plugs. If someone could point me in the right direction, that would help. I've done a google search and searched this forum without luck. Also, the low speed shake (most obvious at about 1 mph) seems to be a common problem. Has anyone else had this on a V6? Thanks for your help.

[dhh3]

Welcome to the forum. No shake from my V6 - 3.6 Pentastar. Which engine do you have and how many miles are on it?

[2004CSOTP]

Welcome to the forum. No shake from my V6 - 3.6 Pentastar. Which engine do you have and how many miles are on it?

It's a 6 cylinder, I believe a 3.6, and it has 88,000 miles on it.

[2late4u]

check thur the forum for the spark plug info i remember someone putting info on how to get to them...

[2late4u]

Hello all,

This is my first time posting on this forum. I have a 2012 DJ with the V6. It was at the dealer a few weeks ago for misfiring. They replaced an ignition coil on cylinder number 3 and recommended I replace the spark plugs, air filter, and flush the fuel system. I thought 100 bucks for an air filter and 500 to change spark plugs was too much so i just had them change the coil. When I got it back, I replaced the air filter myself (12 bucks) and ran fuel system cleaner through it. The misfire and low speed shaking were gone, but now the shaking is back. I'm going to change the spark plugs, but I'm not convinced that's the cause of the shaking.

First, I can't seem to find information on how to remove the intake manifold to get at the spark plugs. If someone could point me in the right direction, that would help. I've done a google search and searched this forum without luck. Also, the low speed shake (most obvious at about 1 mph) seems to be a common problem. Has anyone else had this on a V6? Thanks for your help.

ask journey SeXT...for any info he posted info on the 4cly for a fellow member and he said he planned on doing his 3.6...too much into the engine for me think ill let a mechanic do it...

Journey_SeXT Journey_SeXT

[jkeaton]

Not sure there s a write up on here. You could be the first. Take lots of pics.

[cplmadison]

take one plug lead of, start the engine, listen to engine noise, turn engine off , put plug lead back on. repeat until you have removed them all..

each time you remove a plug lead you will notice the engine sounds different a bit rougher as its running on less cylinders

when you get to the faulty plug you will notice as removing the plug lead will make no difference to the sound of the engine, thats the faulty plug

or just change them all :P get yourself a plug spanner, pull the plug leads off, unscrew the old plugs, screw the new ones in (but dont over tighten)

thats pretty much about it :P

you could always take the plug out 1 by 1 leaving it attached to the plug lead and see which ones are sparking and which ones arent that works too

Edited March 15, 2015 by cplmadison

[Journey_SeXT]

Upper

UPPER

1. Disconnect and isolate the negative battery cable.

2. Remove the engine cover (1).

   

Remove the resonator (1) (Refer to Engine/Air Intake System/RESONATOR, Air Cleaner - Removal).

Disconnect the electrical connectors from the Manifold Absolute Pressure (MAP) sensor (1) and the Electronic Throttle Control (ETC) (7).

Disengage the ETC harness from the clip (8) on the throttle body. Disengage the wire harness retainers (4 and 5) from the upper intake manifold near the MAP sensor and reposition the wire harness.

Disconnect the following hoses from the upper intake manifold:

• Positive Crankcase Ventilation (PCV) (3)

• vapor purge (6)

brake booster (2)

Disengage the wire harness retainer (4) from the upper intake manifold support bracket (5).

Disengage the wire harness retainer (3) from the studbolt (2).

Remove two nuts (1), loosen the studbolt (2) and reposition the upper intake manifold support bracket (5).

Remove the nut (2) from the support bracket of the heater core return tube (1).

Remove two nuts (1), loosen two studbolts (3) and reposition the two upper intake manifold support brackets (2).

NOTE

The upper intake manifold attaching bolts are captured in the upper intake manifold. Once loosened, the bolts will have to be lifted out of the lower intake manifold and held while removing the upper intake manifold.

NOTE

Exercise care not to inadvertently loosen the two fuel rail attachment bolts that are in close proximity of the upper intake manifold attaching bolts.

Remove seven manifold attaching bolts (1) and remove the upper intake manifold (2).

Remove and discard the six upper to lower intake manifold seals (1).

Cover the open intake ports to prevent debris from entering the engine.

[Journey_SeXT]

3.6L

3.6L

NOTE

The LH ignition coils are shown, the RH ignition coils are similar.

1. Remove the ignition coil (2) (Refer to Electrical/8I - Ignition Control/COIL, Ignition - Removal).

   

2. Prior to removing the spark plug, spray compressed air into the cylinder head opening. This will help prevent foreign material from entering the combustion chamber.

   CAUTION

   The spark plug tubes (1) are a thin wall design. Avoid damaging the spark plug tubes. Damage to the spark plug tube can result in oil leaks.

Remove the spark plug from the cylinder head using a quality thin wall socket with a rubber or foam insert.

[Journey_SeXT]

3.6L

3.6L

1. Check and adjust the spark plug gap with a gap gauging tool (1) (Refer to Electrical/8I - Ignition Control - Specifications)

   

   CAUTION

   Special care should be taken when installing spark plugs into the cylinder head spark plug wells. Be sure the plugs do not drop into the plug wells as electrodes can be damaged.

   CAUTION

   The spark plug tubes (1) are a thin wall design. Avoid damaging the spark plug tubes. Damage to the spark plug tube can result in oil leaks.

2. Start the spark plug into the cylinder head by hand to avoid cross threading.

   CAUTION

   Spark plug torque is critical and must not exceed the specified value. Overtightening stretches the spark plug shell reducing its heat transfer capability resulting in possible catastrophic engine failure.

Tighten the spark plugs to 18 N·m (13 ft. lbs.).

NOTE

The LH ignition coils are shown, the RH ignition coils are similar.

[Journey_SeXT]

Upper

UPPER

NOTE

Prior to installing the upper intake manifold, verify that the four fuel rail bolts were not inadvertently loosened. The bolts must tightened in the sequence shown to 7 N·m (62 in. lbs.) (Refer to Fuel System/Fuel Delivery/RAIL, Fuel - Installation)(Refer To List 1).

1. Clean and inspect the sealing surfaces. Install new upper to lower intake manifold seals (1).

   NOTE

   Make sure the fuel injectors and wiring harnesses are in the correct position so that they don't interfere with the upper intake manifold installation.

2. If removed, install the insulator (2) to the two alignment posts (3) on top of the LH cylinder head cover.

   

Lift and hold the seven upper intake attaching bolts (1) clear of the mating surface. Back the bolts out slightly or if required, use an elastic band to hold the bolts clear of the mating surface.

Position the upper intake manifold (1) onto the lower intake manifold so that the two locating posts (2) on the upper intake manifold align with corresponding holes (3) in the lower intake manifold.

Install the seven upper intake manifold attaching bolts. Tighten the bolts in the sequence shown to 10 N·m (89 in. lbs.).

Install two nuts (1) to the upper intake manifold support bracket (5). Tighten the nuts (1) to 10 N·m (89 in. lbs.) and tighten the studbolt (2) to 20 N·m (177 in. lbs.)

Engage the wire harness retainer (3) to the studbolt (2).

Engage the wire harness retainer (4) to the upper intake manifold support bracket (5).

Install two upper intake manifold support brackets (2) with two studbolts (3) and two nuts (1). Tighten the studbolts (3) to 20 N·m (177 in. lbs.) and tighten the nuts (1) to 10 N·m (89 in. lbs.).

Install the nut (2) to the support bracket of the heater core return tube (1) and tighten to 12 N·m (106 in. lbs.).

Connect the following hoses to the upper intake manifold:

• Positive Crankcase Ventilation (PCV) (3)

• vapor purge (6)

brake booster (2)

Connect the electrical connectors to the Manifold Absolute Pressure (MAP) sensor (1) and the Electronic Throttle Control (ETC) (7).

Secure the ETC harness to the clip (7) on the throttle body and engage the wire harness retainers (4 and 5) to the upper intake manifold near the MAP sensor.

Install the resonator (1) (Refer to Engine/Air Intake System/RESONATOR, Air Cleaner - Installation).

Connect the negative battery cable and tighten nut to 5 N·m (45 in. lbs.).

Start and run the engine until it reaches normal operating temperature.

Install the engine cover (1).

[Journey_SeXT]

Let me know if there is anything else you need instructions on.

[2late4u]

thanks to Journey_SeXT

Edited March 15, 2015 by 2late4u

[jkeaton]

take one plug lead of, start the engine, listen to engine noise, turn engine off , put plug lead back on. repeat until you have removed them all..

each time you remove a plug lead you will notice the engine sounds different a bit rougher as its running on less cylinders

when you get to the faulty plug you will notice as removing the plug lead will make no difference to the sound of the engine, thats the faulty plug

or just change them all :P get yourself a plug spanner, pull the plug leads off, unscrew the old plugs, screw the new ones in (but dont over tighten)

thats pretty much about it :P

you could always take the plug out 1 by 1 leaving it attached to the plug lead and see which ones are sparking and which ones arent that works too

That's after you get the intake off.

[rolly]

Is that all there is to it?

[2late4u]

lol

[cplmadison]

hey i only have the 2.0 crd diesel version :P just going off memory from when I used to own a petrol car many moons ago... :P coming to think of it I havnt owned a petrol car in over 15 years.. :P but then it is like $9 a gallon over here...

Edited March 16, 2015 by cplmadison

[OhareFred]

Forget it! I'll pay the dealer to do this one! You gotta be kidding me.....

[larryl]

Insane

[jkeaton]

Definitely a weekend job. Lol. Hopefully we will be on our 3rd DJ by the time this one needs new plugs.

Edited March 17, 2015 by jkeaton

[Journey_SeXT]

If I ever do this job I'll post the step by step pics but I'm still a whiles away from replacing them...I'm looking forward to do this job as I'm sure the cost savings and challenge will be rewarding.

[onecrazyfoo4u]

Yeah f*** it. Just trade in the vehicle before it needs new plugs, lol!

Seriously though, this is my 11th vehicle I've ever owned. By far the WORST design to replace spark plugs on. I'm at 83k miles now and getting ready to replace the plugs in a few months. It looks a lot worse than it really will be. Should be able to knock it out in a couple hours.

[jkeaton]

I've had to do this on my Sebring and my sons Tiburon. Both required removal of the intake manifold. Really not that bad. Just take your time and label all connectors/vacuum lines and whattever else needs to be disconnected so it all goes back where it came from.

[Connie Lopez-Lucas]

Hello all,

This is my first time posting on this forum. I have a 2012 DJ with the V6. It was at the dealer a few weeks ago for misfiring. They replaced an ignition coil on cylinder number 3 and recommended I replace the spark plugs, air filter, and flush the fuel system. I thought 100 bucks for an air filter and 500 to change spark plugs was too much so i just had them change the coil. When I got it back, I replaced the air filter myself (12 bucks) and ran fuel system cleaner through it. The misfire and low speed shaking were gone, but now the shaking is back. I'm going to change the spark plugs, but I'm not convinced that's the cause of the shaking.

First, I can't seem to find information on how to remove the intake manifold to get at the spark plugs. If someone could point me in the right direction, that would help. I've done a google search and searched this forum without luck. Also, the low speed shake (most obvious at about 1 mph) seems to be a common problem. Has anyone else had this on a V6? Thanks for your help.

I am having the same problem. I took it to get the engine read and it was also the 3rd cylinder that I am having the misfire on. I can not find any videos on how to take the manifold off to change the coil pack, but I DO NOT want to take it to a local repair because the ones around here are not ones to trust to repair it properly and to be honest about it. I live in a small town. Did you find any solutions?

[Journey_SeXT]

Here is probably the best video you are going to get on a spark plug replacement for a 3.6L engine --> https://www.youtube.com/watch?v=W3SqhKgoRcc