Putting everything back together after a head gasket replacement and was wondering if there’s any risk to the sensor if the connector is left out of its bracket. I feel like that’s the hardest part about replacing it, so what if it’s just left out?

 

I left mine off for a couple of reasons, hard to get to if you need to replace and if you end up with a bad enough valve cover leak it can fill that connector with engine oil.

 

Leave it out.

 

Agreed. Same for the O2 sensor connectors. Leave them off the little brackets but zip tie or twist tie the cables somewhere to ensure the wires can't touch the exhaust manifold.