What are these hoses for?

I am thinking of disconnecting them to ease access to the drivers side o2 sensor connection, which is inconveniently located between the engine and firewall. What they heck are these hoses for?

 

I wanna say they're HVAC related.

 

99% sure those are your heater core hoses. An inlet and an outlet. If you disconnect them, coolant will spill everywhere.


You can also trace them back to see what the other side connects to, and then you will have a better answer

 

That’s what I was afraid of, figured they might have coolant in them.

 

The metal lines?

 

Coolant hoses for your heater, you can pinch them off with a needle nose vice grip or hose pinch off pliers and disconnect them without losing much coolant but be careful not to mess up the tubes to the heater core as you have to pull the dash to fix that.

 

Just pinch the rubber hose not the steel part....

 

For sure
Pinching the tubes would be a moment.

 

Don't remove them, they are a bastard to bleed and you'll spill coolant on the exhaust.

Try to go through the fender, remove the cover on the drivers side behind the tire.

 

I always liked the fact that they gave you a way to bypass a leaking heater core.

Brilliant forethought so you're not stranded should the unthinkable happen.

 

In your best interest leave them alone.

 

Yeah, I’m not messing with them.

 

If you are referring to the O2 sensor seen in the pic, I can tell right now that removing those hoses have zero effect on the level of difficulty in removing the sensor(assuming yours a 4.0). Never had to replace that sensor but try a O2 sensor socket with a wobble head adapter either from the top or under the vehicle to access it.

 

I was having difficulty reaching the connection where the o2 sensor plugs into the wiring harness, but if crawl underneath the truck and reach it’s actually really easy. I replaced both upstream sensors in no time once I realized that.