The engine trembling after my replacement

How to Change Rear Spark Plugs on a 2000 Ford Taurus, with a Duratec Engine,Without Disturbing the Upper Intake Manifold


1. I only recommend tackling this job, if you have a 3/8-in. drive Craftsman 3-piece quick-release extension bar set or equivalent, 3/8-in. universal joint, 3/8-in. drive ratchet, 3/8-in. drive torque wrench (calibrated in inch-pounds), 3/8-in drive 8mm socket, 5/8-in. spark plug socket with sponge rubber plug holder for a 3/8-in drive ratchet, silicone spray, 10” piece of 3/8-in. I.D.fuel line, Motorcraft Silicone Brake Caliper Grease and Dielectric Compound, Motorcraft AGSF-32W platinum plugs (new no. is SP433), and a tube of Permatex Anti-Seize Lubricant (133A). I used factory-recommended plugs, since my experience using cross-referenced plugs has not been good. I definitely didn't want to repeat that experience here. The original plugs were 4-1/2 years old and had 51,000 miles on them. Make sure the engine is “stone cold” before removing any spark plugs or you increase the risk of stripping the threads in the aluminum head.

2. Silicone-spray the sponge rubber plug holder inside the spark plug socket now, so that the newly installed plug will not pull the socket off the extension bar in the spark plug tube later. You don't need to add any more tension to the job, by losing control of anything in the deep spark plug tubes on the backside of the engine. Disconnect the electrical connector to the plug coil on the left rear plug (all work is performed from the passenger side of the engine). Use the 8mm socket and ratchet to remove the hex-head bolt securing the plug coil. Lift ignition coil pack out; clean with a rag and silicone spray; and apply silicone dielectric compound, using a small screwdriver, to the inside of the spring wire going to the plug. Set the coil pack aside for now.

3. Connect the 6” quick-release extension bar to the spark plug socket. Insert into spark plug tube and seat over plug. “Build-up” the extension by attaching a 3” quick-release extension bar. Next, use a ½” drive 15” flex “T” handle, connected to a ½” x 3/8” socket adapter, and remove the plug. A 3/8-in. drive ratchet did not provide enough leverage to remove the factory-installed plug.

4. Once again, connect the 6” quick-release extension bar to the spark plug socket. Insert a new, properly gapped plug in socket and apply a half pea-size drop of anti-seize compound to the threads, making sure not to get any on the plug's electrode or porcelain. As the plug is threaded, the compound will coat the threads. If too much anti-seize is applied, you run the risk of it clogging the threads, baking on, and making it very difficult to remove the plug next time. Install the spark plug into the spark plug tube. Rotate the extension bar and seat the plug, being careful not to cross-thread the plug. Once again, “build-up” the extension, by connecting the 3” quick-release extension bar. Using the 3/8” universal joint on top of the 3” extension bar, attach the 3/8-in. drive torque wrench and tighten the plug by applying 84 in.-lbs. of torque. Use the lower end of the torque specs (7 to 14 ft.-lbs.) because anti-seize lubricant increases the actual torque by around 40%. Reinstall the ignition coil pack, electrical connector, and hex-head bolt.

5. Using this same technique, you will be able to change the rear middle and right rear plugs. On the right rear plug, however, I had to insert the plug into a 10” section of 3/8” I.D. tubing and thread the plug into the spark plug tube. Make sure to insert the porcelain portion of the plug far enough into the tubing, so it doesn't fall off as you're feeding it into the spark plug tube. Space is limited, so take your time. Much of this is done by “feel,” since visibility is poor.

Only use the exact Motorcraft spark plugs that came in your Duratec--no cross-referenced plugs!

I read from a reliable source not to use anti seize compound on spark plug threads as it will result in an incorrect torque when reinstalling and may also provide a circuit path that will result in a miss fire.

If you use antiseize compound, which is a lubricant, you want to reduce the torque specs 25%. This will prevent stripping any threads. That's why I recommended torquing the plugs to the low end of the torque range; i.e. 7 lb.-ft. or 84 lb.-inches. I use a flux brush and very lightly coat the threads with antiseize compound. I've never heard of or experienced antiseize compound causing in a misfire.