Heater Core Second Opinion?

Ok so...it's probably the heater core.

2000 XJ.

White smoke/fog coming out of the side vents sometimes.

Constant fogging on the windshield.

HOWEVER....it still blows hot air, no problem. So am I just in the beginning stages of this? (It's been doing this for...about a year, getting worse lately, don't judge. I'm a super-broke grad student) The fogging gets WAY WORSE if I use the heat so...I don't use the heat. I don't smell antifreeze...I don't think....a few times I've smelled kind of a burning smell but I was behind other older vehicles seriously every time and convinced myself it was them and not me. I do have a film on the window when I try to wipe it down but that might be from the anti-fog spray I've used...or maybe from the heater core.

Flush the heater core?? Any chance of that helping? Or should I just suck it up and take a weekend and pull it apart. I saw a couple threads saying to replace the evap system too while I'm in there? I really, really, really, really do not want to pay someone $700 to replace a $40 part. I've got a PDF version of the service manual and then all the threads with instructions and youtube...

So do I try flushing it first? Any chance I could make things worse that way?? So far I don't have any moisture coming in on the passenger carpet. I read that that was a sure sign but....nothing yet. Just don't want to cause that to happen.

Thanks!

If it is leaking, flushing it will make the leak worse. Been there, done that.

If it is fogging up your windows, chances are it is leaking.

If it is leaking, it will still provide you with heat as there is still coolant circulating through the core.

There is no way in hell I would pay somebody $700 to install a new $40 core. I would buy an OEM core for 1/2 that and install it myself.

Aftermarket cores are a hit/miss thing. Sometimes you'll get a good one, most of the time they will suck. And, all (unless I missed one) are aluminum.

I don't know why everyone complains about doing this job. Yeah, it takes some time. But, it is EASY. Buy a new foam gasket set.

notamos said:

If it is leaking, flushing it will make the leak worse. Been there, done that.

If it is fogging up your windows, chances are it is leaking.

If it is leaking, it will still provide you with heat as there is still coolant circulating through the core.

There is no way in hell I would pay somebody $700 to install a new $40 core. I would buy an OEM core for 1/2 that and install it myself.

Aftermarket cores are a hit/miss thing. Sometimes you'll get a good one, most of the time they will suck. And, all (unless I missed one) are aluminum.

I don't know why everyone complains about doing this job. Yeah, it takes some time. But, it is EASY. Buy a new foam gasket set.

Click to expand...

And that is why I ask before doing things.

Also, like I said I have the PDF of the manual...but I think I want the hard-copy. Do I need the 4 additional diagnostic manuals or is the one main service manual adequate? Any thoughts guys?

Figured if I'm replacing the heater core might as well replace the evap too because....I'll already be in there and my AC doesn't work...I know that's semi-throwing parts at it but...I'd be really pi$$ed if I put it back together and then went to fixing the AC and figure out the evap needs replacing. Pretty sure the AC is the compressor....but..eh.

Any votes against replacing the evap while under there? I can always return the part if you really advise against it.

In the Southeast where A/C is used extensively I would change it.

md21722 said:

In the Southeast where A/C is used extensively I would change it.

Click to expand...

I mean...I'd love to use the AC. It's just never worked. So we can call this a first step in to getting a working AC. :clap: Lol.

Your defrost works with your a/c. When both systems are working properly, the a/c pump will cycle on and off when you are set to defrost. It does this to dry the air. It would take forever to defrost my windows...until I got the a/c fixed. Night and day difference.