You will first need to start from the coil packs on your vehicle. There should be two spark plug wires connection to each coil pack, and three coil packs since you have a V6.
Trace those wires to where they connect to the engine. This will lead you to the spark plugs.
Once you locate the spark plugs, either label with white permanent marker the cylinder each wire is connected to, so you do mix up the spark plug wires upon re-installation. You will also need to label the cylinder number you can number based on observation of cylinder to spark plug wire, then spark plug wire to appropriate coil pack connection electrode. Label the cylinder number on both the coil pack connection electrodes, the cylinder and the wires.
The better way to do this, is to get the Haynes Maintenance Manual for your vehicle Make/Model/Year. Go to the engine electrical section or the engine tear-down section. Look up the diagram which shows you the correct cylinder numbering, the firing order and what spark plug is meant for which cylinder, also with a diagram of the coil pack cylinder numbering. This is very important, because when you get the spark plug wires off, they MUST go back on correctly or you will get cylinder misfire since the spark plug wires are not installed in the correct configuration in relationship to firing order.
Once you are familiary with where all spark plug wires go and which cylinders are what numbers, go ahead and carefully pull off the spark plug wires from the spark plugs. There is a housing around the plug wire connections to the spark plug. You can also buy a tool which is designed to pull the wires off the spark plug with minimal stress to the spark plug wire. You might want to replace the spark plug wires while you are going about doing this. Because you will have to eventually and it will be more work to do so again later.
I suggest you buy a new set of spark plug wires for your vehicle Make/Model/Year, along with new spark plugs. Make sure the spark plugs are the correct model based on manufacturer for your vehicle, with spark plug electrode gap measurement stamped on the package. If it isn't you can look it up either in an Automotive Spark Plug Reference Guide, or the clerk or licensed mechanic selling you the spark plugs if bought at a parts store can tell you, or you can find it on the Catalyst Sticker on the front of your engine compartment on your vehicle. Also you can look it up in the Internet based on your vehicle Make/Model/Year. You will also need an incline-type spark plug feeler gauge so you can correctly gap the spark plug electrode before installtion. Lastly, you will need a little tube of die-electric grease also.
After you get the spark plug wires removed from the spark plugs and the coil packs, set them aside in a neat, organized manner, paying attention to which cylinders they came off from. Because when you put on the new spark plug wires you will want to match the same lengths as the old ones, so the repair is made in the precisely correct manner.
Now get yourself a 5/8" spark plug socket, which usually comes with basic hand tool ratchet sets from Craftsman. Use a 3/8" drive ratchet, with 3" extension onto it, but tape the extension with black electric tape, or when you go to install spark plugs, that rubber insert will grab onto the spark plug tightly, and when you go to pull the socket off, the socket will stay on the plug, while the ratchet and extension will come off.
If you have compressed air available, blow off the areas around the spark plugs after you get the wires off of them, of any standing dirt or debris. This minimizes the chance of dirt or debris from entering the cylinder, when you remove the spark plugs. If you don't have compressed air, at least try to wipe away any standing dirt or debris around the spark plug if you see any.
Now disconnect the black Negative (-) battery terminal wire ONLY!!!!! NOT the Positive Red Wire (+). This will de-energize your vehicle systems, as to prevent accidental electrical shorts and shocks, when you are working. Cover the negative battery terminal wire (-) metallic connecter end with a plastic bag to avoid accidental electrical shorts and arcing.
Put the spark plug socket onto the spark plug, make sure the socket goes all the way down the plug till it stops. Use your body weight and yank on the ratchet counter clockwise until the spark plug comes loose. Then proceed with unscrewing it from the cylinder head. Repeat this process until all of the plugs have been removed. Lay the old plugs to the side, neatly in an organized manner as you did the old spark plug wires, in reference to the cylinders they came off from. You can also use a 1/2" drive large ratchet with an adapter on it so it can connect to a 3/8" extension or socket. This will make it easier to loosen the spark plugs. Observe the old spark plugs, if their spark-side ends are a light brown color, or brownish, then that is a sign that everything is normal within your cylinders combustion chambers. If not, you could have a higher compression ratio engine, using too low of octane fuel causing detonation, which will make the plug ends more a lighter or even an off-color not in the brownish coloring. Or you might have poor air flow into the cylinder from poor air filter/induction system servicing. But take note of, if you see any severely damaged spark plug spark-side ends. If you don't see anything like that, then move on to spark plug replacement.
Now before you install your spark plugs, you need to gap the spark plug electrode at the spark-end side of the spark plug with your feeler gauge to the correct spark plug electrode gap, for your new spark plugs, before you install them. Never trust the gap put on by the factory and the distribution handling of the spark plugs. You are to gap them to the correct electrode gap, and verify that they are correct prior to installation. If the gaps are higher than the required gap, carefully and gentley press on the electrode arm downward with your incline-type feeler gauge back surface. Then insert the feeler gauge and move it up the incline until the correct gap measurement is reached. Repeat this process until all of your new plugs are correctly gapped.
Next, lay the new spark plugs on a platform which is clean, dry and free of any debris. You might want to place your new spark plugs on a little table with a clean towel on it.
Go ahead and install all of the new spark plugs into the cylinder head on the engine. You of course know by now there is a front bank of spark plugs and a rear bank of spark plugs. Since the engine is configured for front wheel drive, the flywheel is to the right side while the cylinder heads are arranged front to back, not side to side as on back-wheel drive configured engines, where the flywheel is in the rear. Install all of the spark plugs on both the front and back cylinder banks. You will need to probably remove the extension on some of the spark plugs for the rear cylinder head bank, in order to gain access. Make sure you apply enough torque to install the spark plugs into the cylinder heads, tight enough, but not over-tightened. Use your judgement. 10 foot-lbs is plenty of torque to install the spark plugs with.
After you are done installing the spark plugs, apply a little die electric grease onto the spark plug outside electrode tips where the spark plug wires connect to. Also apply
die-electric grease onto the coil pack electrode tips, where the spark plug wires connect to.
Now, open up the the package for your new spark plug wires. Lay out the new spark plug wires in accordance to the lengths of the old spark plug wires. Match them up so you replace the new spark plug wires in the exact same lengths as were on before.
When you have matched them to the old spark plug wire lengths according to cylinder, install the spark plug wires in accordance also to the cylinder numbering in relationship to the firing order and the correct numbering on the coil packs. This diagram in isn the Haynes Maintenance Manual for your vehicle Make/Model/Year. Install the spark plug wires in accordance to the MM diagram cylinder/firing order/coil pack cylinder numbering.
After you are done with that, make sure you rig and secure the spark plug wires back into the grooves the original spark plug wires were secured into. The idea is to NOT have any spark plug wires touch any hot exhaust components or heat shields, and that they are routed in a neat, organized manner, away from dragging onto anything, suspended above hot exhaust components and electrical, communication and radio/antenna systems. So there is no Electromagnetic Induction leaks between the wires and to to the radio. The wires should have a little bit of slack and curve to them, on tight enough, but slack enough for some flexibility, movement and curve.
Make sure all spark plug wires are correctly installed from the correct coil pack cylinder numbers, to the correct corresponding cylinder numbers, in accordance to the cylinder configuration numbering and firing order. Verify you have done it correctly after you finish installing the spark plug wires. This will prevent accidental misfires and possible damage to your engine pistons and associated engine electrical and ignition systems.
Once you have verified correct spark plug installation without a doubt, go ahead and carefully remove the plastic bag from the negative battery terminal wire (-) metallic connector end, and connect it to the battery. negative (-) terminal. Tighten the connection to the battery negative terminal securely, but do not over-tighten.
Keep your hood opened. Go ahead and start the engine. Verify that there are not any warning lights that stay on the instrument console inside the vehicle. Let the engine run for five minutes, observe if any warning lights come on, on the instrument console inside the vehicle. Also leave the engine running and visually observe if anything unusual is happening with the engine, listen for any unusual sounds too. If everything is ok, then shut off your engine. Close the hood. You are done.
This completes the correct procedure for replacing the spark plugs on your vehicle.