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Which Sparks/plugs should I buy

I am going to have the spark plugs and wires replaced in my 2002 Kia Sedona. the place doing the work will let me bring in my own parts. Well looking at autozone they have plugs priced anywhere from $3 up to $11 per plug. For the wires they run low of $35 up to $60. How do I decide which plugs/wires are the best purchase price wise and performance wise for my mini van that is 10 years old and has 147,000 miles on it. It is a 6 cyclinder.

Buy NGK OEM replacement plugs. Your 2002 should not need wires. It should be Coil-On-Plug (COP).

Okay what is a COP and should I consider replacing those or are they replaceable even?

Okay what is a COP and should I consider replacing those or are they replaceable even?

They should NEVER need replacing.

The old ignition systems had ONE coil and a distributor that directed the spark to the spark plugs.

Now there’s a Coil per spark plug and it’s controlled electronically.

All you need to do is replace the plugs. Nothing else. NGK are probably the OEM replacement plugs. Stick with them. Don’t have to buy them from the dealer…Most decent parts stores carry NGK plugs.

Autozone does carry them but a number of different types and prices. What is the difference between the 2.99 each ones or the $14 ones?

I hope these are not the original plugs in that vehicle. If so, they should have been changed about 80k miles or more back.

If they are the originals and the shop tells you the plug replacement will be more expensive due to chasing the threads or installing plug inserts due to damage from removing the old plugs do not think that you are being ripped off.

Leaving plugs in place for an eternity often comes with a price due to their seizing in the threads.

The safe bet is to always use the same brand and type plugs the engine came out of the factory with.
There should be a sticker on the underside of the hood saying the brand and part #.

The cheaper ones are probably plain old copper core plugs and the more expensive ones would be Iridium, etc. Platinum and Iridium plugs do not provide any benefit other than lasting, on average, longer than a copper core plug.

I have no idea the age of the plugs. I have had the van for about a year plus and about 12,000 miles. It runs great and gets the gas milage it’s suppose to and from looking at the van and it’s care I gotta think at somepoint the previous owner, and there was just one, did change out the plugs.

“It runs great and gets the gas milage it’s suppose to and from looking at the van and it’s care I gotta think at somepoint the previous owner, and there was just one, did change out the plugs.”

Do you have two Kia Sedona vans?
I ask that question because in two previous threads, you have complained about the engine “sputtering”, and then getting a trouble code for cylinder 6 misfire. That is not what I would consider a vehicle that “runs great”, but I guess that we have different definitions of “great”.

Also, you previously stated that you had no idea if the plugs had ever been replaced, and several of us advised you to first replace the plugs in order to remedy the misfire condition, and that, if the new plugs did not help, then it would at least be easier to find other causes for the misfire.

Are we talking about the same vehicle?

It did the sputtering for just a few miles and then stopped, the CEL went off and has not come back and the engine is humming along. Over the 12,000+ miles I have driven it the engine has always started, never sputtered or anything execpt for a few miles on the day the front drivers side wheel came off due to me not tightening it down enough. I am looking into getting the plugs replaced but may have to save a bit as the Dealership says teh back three are a pain to get to and want $300 to replace the 6 plugs.

I guess I would be more concerned if the sputtering had continued and the CEL had returned, but it has not so I just wonder if something besides a bad plug caused the brief sputtering.

The Van has had zero issues engine wise outside of having to replace the crank shaft sensor and starter which to me is something that would need replacing on a van with 147,000 miles on it. Besides those two things the engine has been purring along.

“I am looking into getting the plugs replaced but may have to save a bit as the Dealership says teh back three are a pain to get to and want $300 to replace the 6 plugs.”

Yes, the rear plugs are very difficult to access, thus leading to high labor costs.
However, replacing just 3 plugs is…NOT a good idea.

In fact, I think (somebody can correct me if I am wrong) that the #6 cylinder is in the rear bank of this engine. In other words, your plan would skip the spark plug that is most likely causing intermittent problems at this point. Intermittent problems soon become chronic problems–especially in the case of things over-aged spark plugs.

Incidentally, the corrrect brand and model specification for your plugs can be found in the Owner’s Manual.
Because engines have a strange way of not running properly with plugs other than the OEM type, I urge you to use the same ones listed in the manual.

I would only have all 6 done. Checked a few non dealership places today and looks like I will be heading back to the dealer, as overall price was only a bit more to have them replace the 6 plugs for $300.

IF you do have a shop replace all 6, ask to see all 6… TWICE now my mom has paid to have the plugs changed on her company cars, TWICE i have purchased the car afterwords, and TWICE the rear plugs were original when I went to pull them.

PS I like the plutnum plugs, single tip…

I always ask for the replaced parts when I get work done, even the belts when I had them replaced.

A wise policy.

I would look at E3 plugs

" The safe bet is to always use the same brand and type plugs the engine came out of the factory with. " I agree there. Many of the plugs sold in the store, are designed to look good and may have a marginal functional advantage, but in real life, the difference between the OEM plugs and the fancy expensive fat wires etc. are looks and price, with almost zero function improvement.

Unless your car is modified, it is usually best to stick with the OEM stuff.

One slight exception would be the fancy long life plugs for those many cars that have hard to reach plugs and they may benefit convenience. However leaving any plug in too long can just make the job and cost far higher in the long run.

The OP asked about coil on plugs (COPs) and I have some experience with them. A COP should last forever, but they don’t. Some cars have more trouble with COPs than others, I have an '04 Ford T’bird and this motor has COP issues.

There is a spring covered with a rubber “boot” that bridges the distance between the COP and the top of the spark plug. These boots deteriorate over time, heat is the main factor. At some point the boots allow the spark to jump to ground without firing the plug and you get a misfire. After a lot of misfires this grounding will burn out the COP itself.

On the back (hard to reach plugs) I’d suggest you replace at least the rubber boots when you change the plugs, and perhaps even the COPs too. A COP is pricey, but a set of boots is cheap and NAPA stores seem to carry boot sets.

As for the brand and type of plug, I buy whatever the owner’s manual recommends and/or what the mfgr used in the motor from the factory.

Your van probably came from the factory with platinum plugs. That’s what I’d replace them with. Platinum plugs are pretty inexpensive and will usually last 100K+ miles. I always put anti seize on the threads of new plugs to assist in removal next time they need to be changed.