So..., I've never had a heater core go so I'm kind of new to what the symptoms are.

I've noticed my temps creeping up lately and a small small amount of coolant useage. For a while there was a very faint smell of coolant when I turned my heater on, and it's now gotten stronger (the smell). Today when I parked my car for 10 min with the windows down (20*c outside) I had fog on the inside of my window when I got back.

The weird thing, is the floor is not wet nor can I feel any moisture if I push my hand up along the trans tunnel under the dash.

Thoughts?

 

Almost sounds like a slightly over heating car pissing steam out of an old heater core. Like maybe you have 2ish problems?

This is coming from someone with the OEM '93 heater core though.

Plug it off, see if the issues continue. If not, yeah, your heater core is probably blown.

 

Well I think I answered my own question. I peeled back the carpet and alas, it is damp. I just couldnt feel it through the thick carpet/padding. So I bypassed the core just now and re-bled. I'll run it like this for a few days and do a coolant pressure test at work to confirm there are no other issues and install a new heater core on the weekend. Here's hoping it dosen't get too cold!...

 

The NB cores are much lighter.

 

Will it fit in the stock location without modification?

 

anyone have pics of a non-jerry heater core bypass?

 

So problem solved. In addition to the heater core I found a very small leak on my rear coolant neck (reroute). The hose had come a bit loose and it was weeping. Retested the system with my coolant pressure tester at work and it holds fine up to 25psi which is as high as I tested. Temps solid at 188* now.