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Discussion Starter #1
Hey guys I have a question. I notice for the last few monthes my car has been missing a bit while idling. But to day while driving the car would sputter at about 2000-4500 rpm's what the hell is that mean. What should I check or replace?
 

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Superman 39 said:
I have the 2.5l V6 and it has 106k
If they haven't been replaced in the last 45,000 miles, do the plug wires.

Before replacing them though, check the spark plug wells for oil (the presence of which indicates leaking valve cover gaskets.) If you find oil in there, get the VCGs replaced before doing the plug wires.
 

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Discussion Starter #5
well mike I already replaced the gaskets because I had oil in the wells. do you think that the oil fried my wires. They are nkg's I really don't like them do you recommend another brand? What plugs do you use? I just ran out side to check the wires and two of them are dead.
 

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Superman 39 said:
well mike I already replaced the gaskets because I had oil in the wells. do you think that the oil fried my wires. They are nkg's I really don't like them do you recommend another brand? What plugs do you use? I just ran out side to check the wires and two of them are dead.
When I posted my reply, I "proof read" it and then looked at your post again and realized your sig indicates you've got NGKs now. When I wrote my reply, I was assuming your might have still had the factory wires. To be sure, the OEM wires are weak, unreliable and short-lived. NGKs are not known for short lives, but when immersed in oil, who knows...

Having said that, I see you've tested (can you describe how you tested them?) two of your NGKs and indeed found them "dead". Did you measure the resistance of the wires, end to end?

A DC resistance check will only uncover one of several failure modes a plug wire can have. Another mode, cracks and insulation breakdowns along a plug wire's length, can let spark energy leak out to nearby engine parts (e.g. valve covers), reducing the spark available to the plug. This is one cause of misfiring and rough running. A DC-open (likely what you measured) can also cause problems because the spark energy now has to jump another gap in the system - where the break is - which again reduces spark plug energy.

The oil in the wells may have damaged the NGKs. I honestly don't know how resistant they are to hot oil immersion but it's safe to assume it's definitely not good for the wires.

If the wells are clear of oil now, put a new set of NGKs on. If you've got oil in there, get that fixed, then put a new set of wires on. While you're in there, you might as well put in a fresh set of plugs too.

FWIW, I too run blue NGKs on my KL03 and have done so for perhaps 3 years now with absolutely no trouble at all.
 

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Discussion Starter #7
the test I ran was rather primative. I started the car and opend the hood. I disengaged the each wire and watch the change in engine performance. with two of the wires there was no change in the cycling of the engine. So The NGk's are good wires then I will have to get another set. What plugs do you recommend? hey thanks for your help. Hey one more thing, I want to get more power out of my engine but I don't want to spend a lot of money so I am ruling out turbos and sc any suggestions. I have an ehaust and intake and looking at headers but confused on which brand to buy if any at all.
 
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