Changing Spark Plugs

[Xavier434]

First, let me just say that I don't know jack about maintaining a car myself beyond knowing the basics about when I need to take it into the shop to get work done. That is something I have been meaning to change for a while and my car needs to have the spark plugs replaced so I figured that might be a good place to start.

What I am looking for here is basically some How To advice when it comes to this matter. I drive a Hyundai Elantra 2005. I would like to know if there is a difference between the brand/quality spark plugs that are available for purchase and which to go with and why. I would like some step by step instructions on how to complete the process. I would also like to know if there are any special tools or other purchases that I need to make. Part of what I need to figure out is if the juice is worth the squeeze on top of everything else when it comes to the cost and labor of doing it myself as opposed to taking it into the shop.

So, is there anyone here who wants to step up to bat?

 

[Vette73]

I have not noticed any major performance difference between plugs and I have replaced hundreds of them. The only plugs I don't like are Autolite. They are just painted threads and I have found them to rust to easily. But even they should work performance wise.

The biggest difference is life span copper is the standard, platinum, and iridium are the 3 most common elements. I run copper in my truck and the Cars have the factory Plat/Iri plugs in them.

As far as how to change best bet is to get a repair manual. The ones they sale at advance/AZ/etc... should be a decent start.

How many miles are on your car? Most copper can do 30-50k and most Plat/Iri can do 50-90k for the most part.

 

[nobb]

Dont take it to the shop, it is so easy to do yourself. I wouldnt consider myself a pro, in fact, I just changed out my own plugs a few days ago and it was my first time. Go to your autoparts store and ask them to search up what plugs will fit. OEM plugs will do just fine. Or if you want to find out what plugs would run the best on your car, I would go read around on car forums for your specific car. I would say copper is best. Doesnt take as much voltage to spark, but platinum and iridium lasts longer (not necessary in my opinion, unless your manual recommends it). Also look at what is the recommended gap for your spark plugs and use the spark plug gapping tool to adjust it. If you dont find this in your manual, you can search it up on the internet or on your car's forum. I think alot of people leave this step out, but I like to do it...just in case. So assuming you already have a wrench set with the spark plug remover attachment, the things you will need from the parts store:

-spark plugs
-spark plug gapping tool
-dielectric grease
-anti-sieze

For the steps, just search up some youtube vids. There are also a ton of step by step instructions on the internet. It should be pretty much the same for all vehicles.

 

[JeffreyLebowski]

whatever you do, do not waste money on multi-pronged plugs.

 

[exdeath]

How many miles? OEM platinum plugs are typically good for 100k, which I assume you are not close to on a 2005. How do you know you need new plugs?

Anyhow, go with OEM spec platinum plugs and make sure they are gapped to OEM spec (can get a gauge for like $.50). If you had a reason for needing different plugs or gap you'd already know why.

Do it when the engine is cold.

Be careful with over tightening or cross threading, it's very easy to damage and strip aluminum heads (recommend a torque wrench if you're not used to it, about ~10-15 lb-ft)

 

[Xavier434]

I broke 60k in miles recently and I have no clue what kind of plugs my car has right now, but I do know that they are factory since I have never replaced them and I bought the car new. My only evidence that I need new plugs is coming from a Goodyear which recommended it to me, but didn't say why and I didn't ask. I would love to be able to determine myself whether or not a replacement is truly necessary though. How do I do that?

 

[mooseracing]

Originally posted by: Marlin1975
I have not noticed any major performance difference between plugs and I have replaced hundreds of them. The only plugs I don't like are Autolite. They are just painted threads and I have found them to rust to easily. But even they should work performance wise.

On cars that are burning slight amounts of oil or running rich, coppers can make a huge difference. I've had vehicles that need a hotter plug when going to platinums.

Either way all plugs suck when it comes to threads to me. I use antiseize on all the different vehicles I help maintain and haven't had one come out easy.

Be careful if you car has alum heads, you can pull the threads out while warm or if they haven't been changed in awhile.

 

[boomerang]

Originally posted by: Xavier434
I broke 60k in miles recently and I have no clue what kind of plugs my car has right now, but I do know that they are factory since I have never replaced them and I bought the car new. My only evidence that I need new plugs is coming from a Goodyear which recommended it to me, but didn't say why and I didn't ask. I would love to be able to determine myself whether or not a replacement is truly necessary though. How do I do that?

Look in your owners manual for the recommended change interval for your spark plugs. There's a chance the Goodyear people were looking for some extra income.

Myself, I would suggest replacing like for like. Assuming the plugs do need changing, replace them with the same brand that are in there now. Your owners manual should tell you what plug to use.

 

[zerocool84]

Originally posted by: exdeath

Be careful with over tightening or cross threading, it's very easy to damage and strip aluminum heads (recommend a torque wrench if you're not used to it, about ~10-15 lb-ft)

x10000000000000

I remember when I was 17 I f'd up and cross threaded on one of my bug's aluminum heads. I tried getting it out but f'd it up even more so I just bought new high flow heads.