Broke a bolt on my valve cover and looking for advice

Hello. I've got an '08 Sequoia Platinum that started throwing a P0306 (misfire cylinder 6). It's got 194K miles, so I was hoping it was just time to replace the plugs. Pulled cylinder 6's ignition coil and was greeted with oil. Having never changed plugs on anything with the plugs through the valve cover, and not knowing this was common, I was freaked out. After some reading on here I see this is a common issue, and the remedy is to replace the plug gaskets in the valve cover. So, while removing various fasteners on the valve cover I managed to break the head of a bolt off. It appears to be simply a ground, but I'm paranoid as I don't understand why Toyota would have a standalone bolt for a ground when an inch away is what appears to me to be a perfectly fine bolt to use as a ground. Here's the broken bolt:



This is what it looked like before I broke it:



The wire goes to an attachment point under the air filter box:





I've never removed a bolt that is broken flush to the surface, and would have to buy an extraction kit and pray I don't bugger up the valve cover in the removal process.

Does anyone think there'll be any issues if I attach the grounding wire to the valve cover using the bolt for the water bypass mounting bracket that is to the left of the broken bolt? Or do I really need to use the original mounting point?

Thank you for taking the time to read my post, and I look forward to your suggestions.

 

Use the smallest sharpest drill bit you can, take your time, spray some bolt blaster (bolt anti seize) on it, and use an easy out to remove. Best of luck to ya!!


After re read I imagine that any good ground would work just fine as long as that broken bolt is not part of tightening your valve cover down?

 

Any ground point will work. Make sure there's no oil, nor oxidation. Attach another ground strap just for sanity, they are like $16 for 3 pcs 24" long on Amazon. The more ground the better.

 

No, it's not part of attaching the valve cover to the cylinder head. That's what made me concerned. I can't imagine why Toyota would have a dedicated grounding bolt when it appears there is a perfectly good grounding point where the water bypass hoses are mounted to the valve cover an inch a way. Waste of money, etc.

Thank you for your reply.

 

Cool, thanks.