2002 4.6L losing coolant

[vhfreak]

Hey everyone, long time no see.

I have a 4.6L 2002 Explorer Limited, and the past few days I'd been smelling antifreeze whenever I got out of the vehicle. Opened the hood a couple days ago and the reservoir was really low, so I filled it up. Got to work yesterday and opened the hood again and had lost a fair amount of antifreeze again, and could see some dripping from toward the back of the engine. Looked like the area around where the heater core goes through the firewall was wet, and I thought I saw some under the passenger trim inside, so I thought heater core, and since there's an Autozone right next to my office, at lunch I bypassed the heater core to keep me going.

Fast forward to today, I had to go run an errand and came back and opened the hood, and I'm down antifreeze yet again. Now I start thinking maybe it's not the heater core, but something in that vicinity leaking. I pulled the hoses that run directly to the heater core, and they both looked good, and now I'm wondering if it's the hose that's goes inbound to the heater core. My problem now is I don't know what that hose is called, and I don't know where the other end of it is. I can feel where it connects to a metal outlet down toward the back of the intake manifold, but I don't know what that is.

Any ideas or suggestions? I'm about ready to dump this vehicle (I've had the tranny rebuilt twice in <2 years), but I'd like to figure out this coolant loss problem before I get rid of it.

Thanks!

 

[vhfreak]

I dried everything off at the back of the engine with the heater core still bypassed, and let it run a few minutes, and that heater core inlet hose that comes from the back of the engine was wet and it was dripping on the ground from the back of the engine. So it's definitely something back there on the passenger side.

 

[fordysenior]

Did the original intake manifold ever get replaced? Was a Dorman intake manifold used --if so, at the back of the manifold, on the passenger side, is a passageway that is capped with a rubber cap and a spring type clamp. That cap and clamp is known to cause problems. And you would lose coolant from there.

It's that thing sticking up on the very back left side

 

[vhfreak]

Yeah, I think that's it. Fortunately I still have that little metal slug that's supposed to go down in there. I suppose putting that in and replacing the cap should be good enough for me to be able to sell it and pass the eventual problem along.

 

[Joe in NY]

the pipe is the heater core return to the backside of the water pump.