1997 Mitsubishi Lancer: Valve Cover Gasket

I'm not familiar with the situation on a Lancer, but normally when you remove the O-rings from its original position, you also replace the O-rings. Especially the ones in places where you can't predict the operating circumstances, like in engines etc. From the outside the O-rings can look okay, but if you take a very close look, using a strong magnifying glass or something, most of the times you will see that the surface of the O-ring is showing small cracks or other irregularities, for instance the material is not flexible anymore, but hardened. I'd say, if you have the O-rings removed, replace them! Also because spare-parts like O-rings are not so expensive.

Correct! Why do the job twice: to correct a cover leak; and again to correct an o-ring leak? ...then again to correct both?

A no brainer really...while the cover is off, use the chance to make everything up to original standard.

Pennies spent wisely now could be pounds not lost regretfully later.

I could not find a listing for the Lancer. But if the lancer uses the 2.0, or the 2.4 engine, both require spark plug O rings. Would you like part numbers for them? I have access to a NAPA website.

When in doubt, do it just like you don't want to pay twice for the same work, especially when the parts costs pennies and the labor costs may rise to the level of an engine overhaul.

TMF