JimOB

OK. Got my new plugs ready to install but what's the gap supposed to be?

My "wonderful" $100 online Bentley manual doesn't tell me nor does my Audi owner manual.

I know that they're probably supposed to come properly gapped by I always like to double check such things myself before installing.

Thanks for your feedback.

Jim

paulroad

.0028 is the gap for a single electrode plug.

JimOB

Is this in inches? Then you probably meant 0.028 or 28 thousandths of an inch?

S4_Cinci (I S'edTFA)

the most often cited one. In reality, either gap should work just fine.

Edd W

the ground bar is shaped with a convex radius to reflect tyhe surface of the centre electrode so you cannot simply slide a feeler gauge in because it will set a gap whihc is too wide.

About .8mm is correct if you ahve some menas of setting it accurately.

A gap which is too wide will retard the ignition timing ab fraction but the EVU will make up for that by advancing it as part of its normal 'advance till it knocks' cycle anyway.