REPLACING THE SPARK PLUGS AND SPARK PLUG WIRES ON A MKIV VR6 12V
The following procedure will outline the steps to replace the spark plugs or spark plug wires on a MKIV VR6. Over time, installed spark plugs will deteriorate or have an excessive amount of carbon buildup, causing decreased fuel efficiency and increased engine wear. The newer platinum plugs will last long beyond their expected lifetime, but that does not mean they should not be changed. The plug wires themselves are typically good for the lifetime of the car, but I would change them at around 100,000 miles. You do not have to change them if you do not want to.
The procedure was based on a '00 MKIV Jetta GLX 12v VR6, engine code AFP, however the procedure should be valid for any VR6 12v engine.
Please be careful when performing the below steps. I always label all my loose parts or place the small ones in plastic bags and label them so I know where they go.
It took me approximately 1 hour to do the entire job. Depending on how good you are with tools, it may take you more or less time.
First, for the parts list. I bought my spark plug cables at http://www.ecstuning.com, but I could not find the spark plugs I wanted there so I bought them at Advanced Auto Parts.
1) Set of 6 spark plug wires ($91.76 at ECSTuning.com, optional)
2) Set of 6 spark plugs - I bought NGK Iridiums @ $6.25 each from Advanced Auto Parts, you may want to go with OEM b/c they are cheaper
1) Torque wrench (low range)
2) 5/8" spark plug socket (or 5/8" deep socket)
3) 12" ratchet extension
4) ratchet to fit your extender and socket
5) Torx-35 bit or small flathead screwdriver
6) Needle-nose pliers
7) Magnetic screwdriver (optional)
8) Special VW Spark plug tool remover - You only need this if your installed spark plug wires do not have a plastic looped pull piece (more on this later)
Please be careful. Do this procedure at your own risk, I can't be held responsible if I have made a mistake in the steps.
Examining your parts
i. Before you begin, first examine your parts to make sure you have all the parts. You should have a set of 6 spark plugs.
ii. If you are going to replace the spark plug wires as well, make you also have a full set of 6 new spark plug wires (see step #25 for a picture)
iii. Drive your car to the location where you will be performing the maintenance. Apply the parking brake and put the transmission in neutral. Make sure you have plenty of light in the area you will be working.
Clearing room to access the spark plugs
1. First, pop the hood and open it up.
2. Remove the two Torx-30 screws holding down the passenger side engine cover.
3. Gently remove the passenger side engine cover by pulling straight up on the cover as shown.
4. Gently pull the 3 spark plug wires from their groove in the front driver's side engine cover.
5. Remove the one Torx-30 screw holding down the front driver's side engine cover.
6. Gently remove the front driver's side engine cover by lifting up slightly on the place shown and pulling it towards the front of the car.
7. Label your spark plug wires by finding the number from your coilpack and following the appropriate wire. I prefer to use the firing order from the Bentley as my nomenclature. Note: it is VERY important that you label your wires properly.
Wrap a small piece of scotch tape around the wire and write the applicable number on it.
If you have OEM spark plugs, they will actually be labeled appropriately, but re-label them anyways. Look towards the boot of the plug for the label.
8. Label your spark plugs by following your labeled wires back to their appropriate sockets. Put a small piece of scotch tape on your intake manifold, and write the number down on the tape. Note: Do NOT attach the tape to the black engine cover, as you will be removing it later on in the procedure.
As a backup check, make sure all the spark plugs towards the front of the car are even numbered, and the ones towards the back are odd numbered. Double check your labeling, because the incorrect wire attached to the incorrect spark plug could cause damage to your engine.
9. Remove the spark plug wires from their grooves in the center engine cover by gently pulling up on the plug wires.
10. Remove the four Torx-30 screws that hold the center engine cover down.
Removing and installing the new spark plugs
11. After you have triple checked your labels on the spark plug wires and the spark plug sockets, find out what type of spark plug boot you have installed. Note: Most post 2000 VR6 model engines will have the loop-pull type of spark plug wire.
If you do not have the loop-pull type of spark plug wire, you will need an additional tool to remove the spark plug boots from the plugs. See Vasillalov's DIY for removing spark plugs on a 2.0 engine: http://dubpix.com/Pics/VORTEX/...G.pdf
12. If you have the loop-pull type of spark plug wire, remove the spark plug wires from the spark plugs as follows: Pull up on the loop until it extends approximately 2".
Then pull up on the loop parallel to the plane of the spark plug. It may require a bit of force, depending on how old the wire is and when you last changed your spark plugs.
13. Continue to remove all of the spark plug wires from the spark plugs. For some of the hard to get to spark plugs, a needle-nose pliers will be useful to extend the loop so you can get a grip on it.
14. Once all the plug wires are removed, set them to the side, ensuring your labels are still intact.
15. Pull straight up on the center engine cover to remove it, and set it aside.
16. At this point, you should be able to see each of the plugs. Before removing the plugs, you should use compressed air to remove any sand, dirt and other debris from around the plugs. If you don't it can fall into the cylinders and cause wear, especially the abrasives.
If you don't have an air compressor, you can use one of the computer duster cans. Just make sure to keep the can as upright as possible and use the thin spray tube or you'll just be spraying propellant instead of air.
Assemble your ratchet, ratchet extension, and 5/8" spark plug tool (or 5/8" deep socket). It will be a slightly tight squeeze to remove some of the plugs, so lightly spray the socket with a silicone lubricant prior to each plug removal.
17. Insert your spark plug tool into the socket for the spark plug. Note: It is important that you replace only one spark plug at a time. This minimizes the time that your engine is exposed to the outside, preventing the entry of foreign objects.
18. Once you feel your spark plug tool bite onto the spark plug, gently remove the plug by unscrewing it counter clockwise. If you are too aggressive you may crack the ceramic crown.
19. When the spark plug is fully unscrewed, withdraw your tool. If you have used a spark plug tool, then most likely the rubber inside the spark plug tool will have removed the spark plug with it. If you did not, then you may need to insert a magnetic screwdriver to remove the spark plug.
20. Remove the ratchet from the extender, and place the new spark plug in the spark plug socket. I used a magnetic screwdriver to guide the new spark plug into the socket.
21. Insert your spark plug tool into the socket for the spark plug. Tighten the spark plug until it is finger tight.
22. From here, you need to read the directions on the new spark plug box. It should have installation instructions, ranging anywhere from a torque setting to a number of turns to tighten. The NGK Iridium plug instructions tell you to tighten either 1/16 of a turn or 1/2 of a turn based on the type of crush washer included with the spark plug. Note: By all means do NOT exceed 25 N-m (18.5 ft-lb). Doing so may strip the threads in your engine block, and you will not be a happy camper.
After you thoroughly understand the directions, install the spark plug. I used a torque wrench to tighten the spark plug to ensure I did not exceed 25 N-m.
23. Repeat the above steps 16-22 for the remaining five spark plugs. Spark plug #4 is notorious for being difficult to remove. When withdrawing your spark plug tool for #4, twist the tool at the same time to work it out of the socket.
Installing / Replacing spark plug wires
24. If you are not replacing your spark plug wires, skip to step 31.
25. Now for the spark plug wires. It is VERY important that you do each wire one at a time so you do not confuse which wire is which. All of the plug wires are different lengths.
26. Using your new spark plug wire, find an old plug wire that most closely matches the length of your new spark plug wire, and label the new spark plug wire with the same number as the old one.
27. Remove the old plug wire from its location on the coilpack. It may take two hands and several minutes of wiggling to remove the plug. I made my life easier by removing the Air Box Filter cover: Steps 21-22 of VgRt6's excellent Water Pump replacement DIY: http://forums.vwvortex.com/zerothread?id=1154344
28. Install the new spark plug wire into the vacant location on the coilpack. As you push it into place, it may make a soft "click" sounds, or no sound at all. Regardless, make sure that it is seated firmly on the coilpack.
29. Repeat steps 26-28 for the remaining five spark plug wires.
30. Re-install your Air Box Filter Cover (if you removed it) and set your new spark plug wires to the side. Re-install the center engine cover with the four Torx-30 screws.
31. Now install the applicable spark plug wire to each spark plug using the labels that you have written. Slide the spark plug boot into the spark plug socket, and press down very hard. The boot may make no noise as it seats onto the spark plug, so tug lightly at the wire once it is installed to make sure it is seated properly.
32. Give each spark plug wire an additional push to make sure each is seated properly onto the spark plug and onto the coil pack. Also second check to make sure the labels match up properly.
32. Re-install the front driver's side engine cover with the one Torx-30 screw.
33. Re-install the passenger's side engine cover with the two Torx-30 screws.
34. Gently reseat the spark plug wires into their grooves in the engine covers.
35. Start up the engine. It should run smoothly and cleanly. If it sounds rough or mis-fires, you have made an error somewhere. Check all your cables to ensure they are seated properly and that your labels match up.
That's it! Email me with questions if you have any, I'd be happy to answer them!
Modified by FaelinGL at 8:16 PM 10-2-2005