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Spark Plugs...a no man's land?

I was thinking about changing my own spark plugs and wireset. Which I have never done before, but there is a plethora of knowledge on it on line and I even found a few videos of “How To”. I also have ye old Haynes Guide. Am I delusional to think that I can do this on my 99 Ford Escort ZX2 2.0 DOHC. Or should I go for it? What is the worst thing I could do to my car and how long of a job is it? Thanks!

This should be easy to do on this engine. Make sure to apply a little anti-sieze compound on the threads of the new sparkplugs before installing them. Also, when replacing the plug wires, do them one at a time. This ensures the correct wire goes to the correct sparkplug.

Tester

No, you’re not delusional, just nervous about the unknown. This is a great DIY job, especially with an inline 4-banger like yours. You have done absolutely the right thing by starting by doing research.

The worst things you can do are

(1) cross the ignition wires up. This can be positively avoided by changing only one wire at a time. Don’t remove them all at once and then start to install the new ones. NOTE: on most modern cars it’s not possible to cross the wires up. But this is a good thing to be aware of.

(2) overtorquing or undertorquing the spark plugs. Invest $25 in a beam-type torque wrench from Sears. The torque spec will be on the side of the plug box as well as in the manual. Torque carefully. Others have differed with me on the importance of a torque wrench, but I think it’s a really good investment, especially for a first-timer.

You’ll do fine.

Probably a good reason to change the plugs but do you have a reason to change the wires? Do you plan on damaging a wire when you remove it from the plug? this is possible.

Yes, an easy job. Be sure there is not any crud in the plug wells before you take the old ones out, blow it out. Use the recommended Motorcraft replacement plugs or the Autolite equivalent. If you use those plugs they will be nickel plated and you won’t need and should not put anything on the threads. Use some dielectric grease on the plug boots. Yes, do use a torque wrench.

You can do this job. The worst thing you can do is misthread a spark plug when you insert it, and over tighten a spark plug to a point where the threads on the motor are stripped.

To avoid the misthreading, put on some anti-seize compound and screw in the plugs by hand first. They should turn in with only a little pressure. If the plugs are in a deep well put a piece of rubber tubing over the top of the plug place it in the hole and twist the tubing to screw in the plug. When the plug is finger tight pull off the tubing and place the socket over the plug and tighten the plug.

You can avoid overtightening by buying a torque wrench. These run from somewhat expensive to very expensive. If you don’t want to invest in a torque wrench when the plug is firmly tightened by hand then tighten another 1/4 to 1/2 turn with the wrench. Unless you are a person who tends to overtighten and strip out lots of screws and bolts you should be ok with the 1/4 to 1/2 turn method.

I would replace the plugs one at a time and replace the old wires on the plugs and when done start the car to be sure it is running smoothly. If all is OK then I’d replace the old wires with new ones, again one at a time. This way you will not get confused and put the wires in the wrong holes or on the wrong plug. When you restart the car it should run smoothly. If it bucks, sputters, and backfires then you have to determine which plug wire is on wrong. If one is wrong, then for sure at least 2 are wrong and that means the car will definately run rough until you get it correct.

Ford’s torque figures are for DRY threads. If you put anything on the plug threads, you must modify the torque figures.

Take a picture of the wires so you will be sure to put them back on right. CW means clockwise amd CCW means counter clockwise (the other way). The video should help.

Simple Spark Plug Change Advice Reads Like Nasa Plans To Build A Space Shuttle And Boosters.

Taken altogether, the advice given would sound extremely complicated, expensive, and scary to a first timer. Besides the typical tools one would use, the changer needs a torque wrench, anti-seize compound, dielectric grease, rubber tubing, a means for taking pictures, etcetera. Add to that a short course on how to use this stuff, like a torque wrench, and determining if my plugs are in a “deep well”, etcetera, and I’d take a pass on it.

Here’s my simple advice since we don’t know Milady’s level of expertise. Work with a person who knows what they’re doing for your first spark plug change. Have them let you do it all. Then you should be good to go . . . until you get a stuck plug, but that is a different issue we’ve offered volumes of advice for correcting.

CSA

It’s just a case of where everyone thinks a mechanics job is such a easy one. But when you get down to explaining step by step tool by tool you start to see that we are all not born with the skills. Maybe just maybe there is a little skill and knowledge involved in doing this mechanics stuff.

I Agree. And I Have Found That “Experience” Really “Is The Best Teacher”.

There is almost no substitute for a little personal help starting the experience building.

CSA

“Work with a person who knows what they’re doing…”

When I was a kid there were people doing all sorts of DIY work and I could watch and learn. Unfortunately that culture is fading. There are so many folks sitting at their computer when they should be out interacting with their neighbors.

You do not want to do it on a hot motor, the threads in the head can come out with the plug.

Eloquently put. In a nutshell CSA just gave a response in which all of my misgivings have been addressed. My level of expertise? I changed a steering wheel column, with a friend, (cause some punk hotwired my car) And I can change my own battery myself, along with the air filter. However, I would like to become “A Shadetree Mechanic” Even if it’s on some amateur level. I’m cheap and I would love to save myself money, my concern is if I mess something up, then I’m gonna spend more money than what I would have saved. But I do love taking stuff apart, and watching how things work, and I am tireless and perhaps even obsessed with research. You could even say I was a little bit bored. Lol. That sizes me up pretty well actually.

Just my opinion, but I never use a torque wrench on spark plugs and do not trust many torque specifications that are given anyway. I feel that many are too high and others are debateable.
In one application (forget which) one specification gives 7 foot pounds and another gives 15+ foot pounds.
Many 1/2" drive torque wrenches are unreliable at around 15 ft. lbs and under in my opinion. The only one I trust for figures that low is a high dollar German made tool I have that is 1/4" drive.

On an iron head 15 ft. lbs. is not a big deal. On aluminum heads it can be, especially if the plugs are tapered seat plugs. Fifteen ft. lbs., or even 12, can pull threads.

With gasketed plugs I run them down till they’re snug and then go about another 1/4 turn. With tapered seat plugs, run them down till they hit and then lightly bump them by hand.
I use a stubby 3/8" ratchet and palm it. This provides all the torque necessary without stripping, or just as bad, pulling the threads. Never had a plug come loose or leak yet and the most important things of all; never a stripped plug hole.

I’m with you. I used to use a torque wrench but have done all my spark plugs by “touch” for about 15 years. I have never stripped or cross threaded a plug and never had a plug come loose. Once you get a feel for the proper torque it just sort of stays in muscle memory.

Milady, Wanting To Save Money And DIY Is Great.

Medical students don’t always practice on live patients, especially well, live patients. That’s where the cadavers come in. Where are the car cadavers? They reside in the “Take it off yourself auto parts recycling yard”. I have one near where I live. That’s where I get many (most) parts and also where I practice a new automotive parts replacement procedure at the same time. I love this place! My yard has cars like your’s (no offense, their’s are dead) waiting in a line for the crusher.

Pack up the tools you think you need, a spark plug socket (or two different sizes), a 3/8" ratchet, extensions, universal, etcetera. Don’t worry about a torque wrench. You won’t need it. Go to the yard looking for a mysterious lost clip or screw (or even a used spark plug) in the engine compartment of a cadaver Escort. Make sure you don’t tamper with a car from which they are going to sell an engine or you’ll tick somebody off. My yard has those in a different area from the crushees. There has to be something your car is missing that’s worth less than a buck, right? While you’re out of sight, over that hill, take out and replace a spark plug. Do the hardest one to access, if one is more difficult.

Addressing your concern that you’ll mess something up and it will cost you more, we’ve all had our little glitches. Sometimes it could cost a little more, but often it’s a learning experience that will help transform you into that “Shade Tree Mechanic”. All in all, you will save far more than you lose. Pretty soon you will develop a sense for what you can handle and what’s best left to the pros.

CSA

Awesome, Awesome Idea, and thanks so much. :slight_smile:

I agree completely with the torque wrench. Never use one for plugs. Just tighten till they are snug…and a little more.

Hmm, I think I stripped a plug hole once. It was an aluminum head on a lawnmower engine we stuck into our home-built mini bike. I was mad because the engine was much lighter than the first one we had in there. Head replacement was pretty easy with a flat-head, one-cylinder engine.

I think it is best to start with lawn mowers, chain saws and the like.