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Spark plug issue

Hey Im sure this has been answered before but Im kind of in a rush.
I changed my plugs a few days ago on my 96’ Taurus GL 3.0L
I checked under my hood to check the recommended gap size and it said .42 to .46, i went with .46. after putting them in i started the car up just fine, but later in the day i noticed when i came to a stop at a red light my car would sputter and my check engine light would start blinking. when id accelerate and drive it again everything would clear up and the light would stop blinking. I didnt change the wires, just the plugs in case you were wondering but im unsure of how much that would influence my problem. Today after work i had alittle trouble starting my car. After a few tries it started and my exhaust smelt rich in gasoline. Did i gap them too much? Should i get new plugs again and regap them? should i buy new wires also?
Is my ignition coil going bad? Any answers are greatly appreciated.

You shouldn’t need new plugs just for a gap adjustment. (I hope they were gapped to .046 rather than .46 btw). The gap, btw, will only increase in size over time so I always gap to the low end of the range. If you start at the high end of the range they get out of adjustment as soon as they get wear.

You should get the codes read to see what they are. They will probably be misfire codes, but even then its good to know which ones. Many auto parts stores will read them for free. They look like “P1234.” (The misfire codes will be P0300 - P0306 on this car).

If this was a brand new problem not there before then the most likely thing is that you either damaged a wire or two or just didn’t get them back on all the way. They have to “click” back into place onto the plugs and coil. You also need to double check that they all went back where they belong (#1 to #1 and so on). If they are the original wires, then just replace them either way.

Presumably you didn’t leave any of the plugs loose? What kind of plugs were they? What did you gap them with?

Are these platinum plugs? They are supposed to be pre-gapped. I always check the gaps, but you need to be very careful when you need to adjust the gap. Use a gap tool that only touches the anode ‘hook’, and never touches the cathode tip. Platinum is a very hard metal, but is also brittle. Adjusting the gap by prying against the tip can crack the platinum tip and wreck the plug. The cracked tip with eventually fall out and the spark plug will fail.

Also, I always replace the wires when dealing with platinum plugs. They’ve been there for 100,000 miles if you use the interval in the manual, and that is long enough. Chances are, they will not survive to the next change interval.

Thanks alot guys! I might just get new platinum plugs cuz i might have screwed up the tips.

My wireset is 40 bucks LOL

Ahhh…yes. BustedK was exactly right to point that out. If they were platinum you actually shouldn’t gap them. So if you did, and you’re not an experienced plug gapper, then there’s a good chance you should just get new ones.

Squeeze me, there was an earlier response to spark plugs that determined spark plug number by gap. In my humble opinion gap should be checked for each plug. Sure they were pre gapped at the factory, but how many dings drops and bounces are you comfortable with. It is so easy to check the gap I am at odds with anyone who calls it hard or not necessary.

The ground electrode, the cathode, is adjustable…The center electrode, the anode, is not…But I have a feeling this problem has nothing to do with the spark gap…I agree with C-roller, set new plugs at the tight end as they will open up as they age… Plug gap is important but not critical with todays high-powered ignitions…1996…Are those wires 16 years old? How many coils are used?

"The ground electrode, the cathode, is adjustable..The center electrode, the anode, is not."
The center electrode is the cathode, the adjustable ground electrode is the anode.

“Cathode polarity is not always negative. Although positively charged cations always move towards the cathode (hence their name) and negatively charged anions move away from it, cathode polarity depends on the device type, and can even vary according to the operating mode. In a device which consumes power, the cathode is negative, and in a device which provides power, the cathode is positive:”

Maybe the labels “cathode” and “anode” should not be applied to spark plugs…How about ground electrode and center electrode?

When gaping spark plugs, no force at all should be applied to the center electrode…Don’t even touch it during the gaping process…

Caddyman"Maybe the labels "cathode" and "anode" should not be applied to spark plugs......How about ground electrode and center electrode?"
I agree; the terms cathode and anode can be confusing.

In older cars, where one coil fed all the plugs, the ignition secondary was wired so that the plugs fired when the center electrode went sufficiently negative with respect to the ground electrode. It was wired this way because the center electrode is hotter (because it is more thermally insulated) than the edge electrode (which is in thermal contact with the engine block), and electrons are emitted more readily from a hotter electrode than from a relatively cooler one. But conventional current flow is opposite to electron flow, which means that, during the initial arc, current flows from the engine block to the center electrode.

In radio tubes and cathode ray television tubes, the heated electrode that emits electrons is called the cathode.

After writing my original reply, I remembered that modern cars often have a pair of spark plugs sharing a single coil. In such a case, one of the plugs fires on a positive voltage swing while its mate fires on the negative swing.

In googling I came across the interesting fact that spark plugs placed in new Ford cars leaving the factory have either the center electrode or the side electrode made of platinum, while the less corroding side is made of a cheaper metal. Evidently it saves on spark plug cost at the factory. Replacement spark plugs have both electrodes made of platinum.

Ford’s “half-platinum” factory spark plugs

I thought most of the cars now had gaps of 60 thousanths? The first thing I would consider would be the plug wires. One not on tight, bad wire, or damaged them while pulling them off. A lot of cars are hard to get good access to the back ones. I’ve been doing plug changes for, hmmm, at least 40 years, but I screwed up my last one trying to get the plug wires seated, and crossing a wire. Cost me $80, a tow, and a new cat. One wire out of 6 and it ran so bad I wouldn’t drive it.

Did you use the same brand (Motorcraft?) and part # plug as the engine originally had?

Cathode? Leave religion out of this.

“But conventional current flow is opposite to electron flow, which means that, during the initial arc, current flows from the engine block to the center electrode.”

Where did you get this from?

“In older cars, where one coil fed all the plugs, the ignition secondary was wired so that the plugs fired when the center electrode went sufficiently negative with respect to the ground electrode.”

What is your definition of older cars. Prior to 1975, the coil was always positive.

Whenever I replace plugs I always carefully check the gap with gap tool instead of a feeler gauge. Also, I apply a small amount of dielectric greese to the plug wire ends.
C. W.

Forget the arguments on cathode vs anode. It’s futile with the various systems in place. The wasted spark systems will have you guys in a tizzy :wink: I’ve learned over the years, the safe bet is to call it the center electrode and ground electrode…

I never trust pre-gapped plugs after finding just one in a box of 4/6/8 way off even though the cardboard cylinder protecting the end was intact and no box damage.

from cigroller…

“If this was a brand new problem not there before then the most likely thing is that you either damaged a wire or two or just didn’t get them back on all the way. They have to “click” back into place onto the plugs and coil. You also need to double check that they all went back where they belong (#1 to #1 and so on). If they are the original wires, then just replace them either way.”

right on

I never use the term cathode or anode when referring to plugs. I usually use the words center electrode and ground electrode.

Keith, I think he’s thinking of “hole flow”. Electrons move from the atoms with the surplus to the atoms with the relative definciency, leaving “holes”.

For the record, an electron is a negatively charged particle. An itty-bitty one compared to protons and neutrons. Electrons always flow from the atoms with the relative surplus (which makes it “negatively charged” to the atoms with the deficiency, which makes them relative to the others “positively charged”.

Anyway, I’m betting that he needs new wires,
And, a quick look-see in the parts catalogs suggests to me that this might be either a distributor based or a PCM controlled system with a coil pack. '96 was apparently a changeover year. If it’s a distributor, a cap & rotor are due also.