Iridium Spark plug Gap

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Hi,

Do Laser Iridium spark plugs usually come pre-gapped correctly?

I got some for my 2009 Nissan Rogue. I got NGK DILKAR6A11 stock #9029.

The largest of my feeler gauge is .70mm and it fits between all of them. Mine are supposed to be .43mm per the field service manual.

I have also read you are not supposed to gap Iridium plugs as it ruins them...
 
Bend the electrode with a needle nose or the special tool. My Gen Coupe plugs come gapped at .044" or so, the car runs best gapped at .030".
 
1mm (milimieter) is .039"

Are you sure you are not mixing inches and mm? .43mm is .017" which is very tight for a spark plug gap.
 
That should be 1.1mm not .43mm !!!

See the 11 at the end of the part number.

that's .043 INCHES GAP.

I don't mean to be a Big Richard, but Are you sure you should be doing the plug job without help?

Maybe a bit gruff since I worked as an Engine Mechanic ( U call them master techs) for years and had to fix more than a few of amateur "Tune Downs"
 
thanks for all the quick replys.

here is the info from the FSM




So yes I read it wrong
tired.gif
 
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For years I always gapped plugs .003" tighter then spec, reason being they do burn/wear
to a larger gap later and can misfire near the end of their lives when operated in extreme cold
or humid conditions, etc.

This still applies to Iridium plugs, they just take 80 to 100K miles to get to that point,
wear on the iridium is hard to see without a good magnifier!

But yeah, make sure you don't mix up metric and inch gaps! LOL
 
Funny, I just gapped some iridium plugs...

First, feather the edge on the feeler gauge with a little 600 grit wet/dry ssandpaper. I found mine to be curled up.
Note the shiny edge.

To open the gap, insert the tail into the hole (insert joke here), and hook the electrode on the lip.
Push gently on the tool, gap will open without touching the tip.
To close, push electrode gently against a hard surface...

Note that these are 8 heat range plugs, the OEM is 7, I went colder, less insulation, more heat is transferred to the head...


 
I've only changed iridiums less than 10 times but I've never checked the gaps. Just inspect them for gross damage and install them. Buy the same ones as what came from the factory.
 
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