Replacing Spark Plugs 04 2.7 Sonata

[jtayloraz]

I have a 2004 sonata 2.7 v-6 I've been told the plugs should be changed @ 60K.
Is this accurate? I'm reasonably sure I can handle the job but where do I begin?

Thanx in advance
Joe

[SuperChris]

http://www.hyundai-forums.com/t20155-how-t...spark-plugs.htm

Its easy. If you want to do it fewer times....get the Bosch +4. Some here will say no and you should get NGK because that is "recommended."

What is the first thing to wear down on a spark plug? Now think of having 4 of them to wear down.

Electricity jumps between the path of least resistance....when one of the prongs wears down, then the spark will jump to the next good one.

Trust me, when you have to yank the upper manifold up and away....you will want to do it as few times as possible.

Also, have you changed the timing belt yet? Ooh, there's a fun one.

Chris

[ssonata78]

You may need a plenum gasket if you feel the need to replace this metal style gasket. I personally lift up on the intake manfold enough to get it out of the way to get the back plugs. Im not sure how the 04 is but there were numerous connections on the back between the engine and firewall. A simple engine cover made of plastic that appears to be there for looks and a few bolts,nuts holding the intake on. Do the wires at the same time to save you later from troubleshooting and thinking it might be wires(remove the possibility). I use dielectric grease for .99 cents from the counter for the wire boot/plug tip connection. Check your gap on the new plugs. Have fun.

Steve

[iam4uf]

I followed directions and all went well. After putting everything back the car would not idle right, then when I pressed the gas the car would accelerate so much I had to shut it off. I called a mechanic friend of mine and he told me the plenum gasket is raised and when you tightening it down it crushes it and is only made for one time use. He said it was taking air that is why it was running so bad.I took the plenum back off and put a new plenum gasket in and car ran perfect. So, my suggestion is to replace the gasket.

[SoNic67]

I hope you didn't use the Bosch 4+ ones. I did it on a 2.5 V6 Sonata and in 2 weeks they needed to be changed.
Now I use NGK Iridium Laser for some 50k miles...

[MyKids04Sonata]

I AGREE with SoNic67 ... DO NOT USE BOSCH... The engine was designed to work with either NGK or Denso plugs... The Bosch plugs use a strange way of gapping the center electrode to the outer grounded electrode.. This has been proven to cause mis-fires and CEL codes...
The iridium NGKs are fine but may be overkill (and more costly) for a high mileage car that you may not keep for another 100k miles... These engines (Hyundai/KIA) can do 300k miles if cared for so Iridium may be what you want.
Dave

[nightflyer87]

Well, now I'm scared to put the Bosch Iridium plugs I bought in my car. I know better than to go cheap and I had found out that these engines work much better and last longer with Iridium plugs. These were the best ones they had in my area without a special order.

[johnaauld]

Originally Posted by nightflyer87

Well, now I'm scared to put the Bosch Iridium plugs I bought in my car. I know better than to go cheap and I had found out that these engines work much better and last longer with Iridium plugs. These were the best ones they had in my area without a special order.

Can you return them and reorder? NGK iridium really is the way to go.

[SoNic67]

Actually the price difference is totally worth it because of labor involved and possible plenum gasket replacement (I did it on mine twice - once I put Bosch in, once when I replace those with NKG Laser Iridium's).
Don't get me wrong: Bosch 4+ worked perfect in my Mercury Sable DOHC, but for some reason didn't in my wife's 2.5L DOHC Sonata, I got a CEL in 2 weeks.

[jsinton]

Why play with fire? Your car is engineered to use a certain specification plug. Just use the OEM stuff unless you like trouble. Don't listen to people tell you "it's easy" either. See what happened?