Is my head gasket blown ? Need help pls

[T.Yazar]

Hi

I have changed the sparkplugs 3 monts ago and I noticed that the only first hole was a litle bit oily but the plug ( plugs ) was clean. Assumed that this was maybe a oil spill when filling

I cleaned up and changed the plugs. Becouse I have no torgue wrench did this by hand .

Today I wanted to check for oil in the sparkplug holes and yes they have all oil in them except for the last one

My question is can there be oil in the sparkplug holes becouse under tightening of the plugs ? Or can there be another reason for it ?

Thx

[Joshdub]

It is most likely the valve cover gasket that is leaking.

[T.Yazar]

Yes sorry I meant valve cover gasket ! I also think that but is it possible it leaks because under tightening of the plugs ?

And can low mpg caused by valve cover gasket leak ?

Thx

[Joshdub]

Under tightening the plugs will not cause a valve cover leak. And I don't think a small valve cover leak will cause a noticeable drop in efficiency

[admranger]

I'd change the valve cover gasket.

Get a torque wrench at Sears or even Harbor Freight. They aren't that expensive.