Thread: What plugs do you like?

What brand spark plugs do you use?


Any reason to go with anything but AC Delco platinums? I believe that's what was in there from factory.


My car has recently been misfiring but throws no codes, my first stop is going to be the spark plugs.

throw some stock plugs back in it.

On a 3.1L use stock unless you got something else going on.

Before you do that...have you ever seafoamed the thing? Especially with it's age...it might just be a sticky valve or another valvetrain competent.

I've run seafoam through intake manifold vacuum. Plan to try again.


Have you used it in the oil? A bit of quiet lifter tick but it is not terrible.

It knocks like a bastard when cold but "it's just a little piston slap, it's still good! it's still good!"

yeah the 3100 ticks and slaps and sounds like it misses
and when its cold it sounds and shakes like a mother ****er
the stock plugs or ngk platinum is what i run, these motor arnt too picky they just sound like they run terrible all time the no matter what plugs they got

It's amazing how well the engine performs when you're actually out cruising. 60-70kph and it's smooth as glass

Originally Posted by 3100sfi

Any reason to go with anything but AC Delco platinums?

Platinums **** the bed. Try stock AC Delco iridium plugs.

I know what I normally do on an iron-headed motor, but do you normally use antiseize on plugs for this motor?

Do you do it when completely cool?

Originally Posted by 3100sfi

I know what I normally do on an iron-headed motor, but do you normally use antiseize on plugs for this motor?

Do you do it when completely cool?

Some people use anti-seize. And I'd use it if I wanted an iridium plug in there for 100,000 miles. If you're swapping plugs every 15k or something like that, it's not enough time for them to seize.