My Fj just hit 265k miles, I found a leak the other day of oil in the spark plug holes from the head cover gasket on the drivers side. Are there going to be any technical steps to take before removing any parts around the head covers? I've tried to DIY things in this fj and ended up with a check engine light coming on. Before I open all of this up is there anything that I should look out for that I can break or sensitive enough to turn on the check engine light? Are there gaskets, vacuum lines, or anything else that can cause issues. My Fj is my only vehicle at the moment so if you've changed head cover gaskets on the 1GR-FE engine I'd like to hear about it. There's very little information about it online. Its a 2011 FJ, 1GR-FE engine w/ 265k miles. Any information that you can share before I go and open it up would be appreciated! Thanks.