Spark plug torque?

[MS6_OH]

I have a slightly rough idle and a bit of a putt putt putt coming from the exhaust at idle. Took it to the dealer and they said they couldn't find anything (I know it doesn't feel the same, I drive the car everyday) So I ordered some stock ngk replacement plugs to see if I have a miss somewhere. What do you guys torque a conical, no gasket type plug to? Just finger tight and then the 1/16 turn as recommended by ngk?

2006 Mazdaspeed6 42k miles

Thanks

 

[MS6_OH]

on a side note to this, is it normal to have a slight putting at idle, and small popping on deceleration? I've seen other threads and complaints for this but with a modded exhaust that doesn't have enough back pressure. My exhaust is stock.

 

[sharky]

Go with what is recommended. You only need it tight enough that it isn't going to back itself out, but not so tight that you risk stripping the threads.

I think with an Aluminum head you'd be safe between 7 and 14lb-ft.

 

[MS6_OH]

thanks sharky. Thats what I'll do, going to change them out tomorrow and see if it makes a difference. Going to stretch the coil springs a bit as well. Hopefully it helps with the idle and exhaust putting/popping. They aren't really loud noises, but its definitely idling differently than it did.

 

[MS6_OH]

changed them out today, pretty easy job. didn't really change the idle/etc much. The old plugs didn't look to bad, just a bit of black carbon build up about 4 threads high on the plug. Is it common to have oil on the couplers attaching to the intercooler?

 

[Qwik6]

I have always had a slight bit of oil sitting in the couplers. More so when I turned up the boost. Its common.