That sweet, sweet smell of a leaking heater core

96Firebird

Diamond Member
Nov 8, 2010
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Past couple days I've noticed a smell in my 2003 Park Ave, especially when I first get in it (after having it warm up with remote start). Very prevalent on the passenger side, even when the car has sat for a couple of minutes. No wet floor or fogging of the windows, but even with my cold I can slightly smell the anti-freeze. It almost smells like chlorine.

Anyone know how hard it is to replace the heater core in this car?
 

monkeydelmagico

Diamond Member
Nov 16, 2011
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Ugh. Not really hard just incredibly time consuming. You will probably have to take the dashboard partially out to get at it. I've done the job on a crown vic and did not enjoy the yoga. If I were you I'd shop it around and see if you can get someone to do it for reasonable price.
 

Rifter

Lifer
Oct 9, 1999
11,522
751
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Yeah not sure of that exact model but it isnt going to be easy. Like said above will likely have to pull apart that whole side of the dash to get to it. Be careful not to break any plactic clips holding the dash together. Not hard just time consuming.
 

MtnMan

Diamond Member
Jul 27, 2004
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Some vehicles also require the opening of the A/C system, and recharging that also. That was my luck on my Dodge truck.
 

96Firebird

Diamond Member
Nov 8, 2010
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I had a co-worker take a whiff because my nose is clogged from a cold. He said it doesn't really smell like coolant, more like moth balls. I'm going to try changing the cabin filter before tackling the heater core, its just weird that it started happening out of nowhere.

I'm really hoping it isn't the heater core, but I don't know what else it could be...
 

IronWing

No Lifer
Jul 20, 2001
73,436
35,055
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When the heater core went out in my Olds, the mechanic told me it would cost more than the car was worth to fix it and just bypassed the core entirely. I live in Tucson so lack of a heater wasn't terribad.
 

BUTCH1

Lifer
Jul 15, 2000
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Some vehicles also require the opening of the A/C system, and recharging that also. That was my luck on my Dodge truck.
Yup, my current Chevy is like this as well, thank God it's still holding up. After swapping out 3 of them in my Escort I am religious about coolant changes. Even a small vehicle that did not require AC pump-down took 16 hours to complete, my hands were brutalized LOL, the entire dash had to come out, steering wheel, center console, ect. 2 shops wanted around $550 for the job, I found out why!.
 

MtnMan

Diamond Member
Jul 27, 2004
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Yup, my current Chevy is like this as well, thank God it's still holding up. After swapping out 3 of them in my Escort I am religious about coolant changes. Even a small vehicle that did not require AC pump-down took 16 hours to complete, my hands were brutalized LOL, the entire dash had to come out, steering wheel, center console, ect. 2 shops wanted around $550 for the job, I found out why!.
After a bit of research to what was involved, I paid to have mine done, money well spent.

The most notable thing after it was changed is the heat output. My truck used to keep me comfortable in really cold weather (teens and 20's), but with the new core it will run me out and I end up turning the heat down after a bit. I never asked the guy that did it, but I'm guessing he went with an after market instead of an OEM core.
 

BUTCH1

Lifer
Jul 15, 2000
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After a bit of research to what was involved, I paid to have mine done, money well spent.

The most notable thing after it was changed is the heat output. My truck used to keep me comfortable in really cold weather (teens and 20's), but with the new core it will run me out and I end up turning the heat down after a bit. I never asked the guy that did it, but I'm guessing he went with an after market instead of an OEM core.
I used one from Autozone for my Ford with a lifetime warranty, thing is it's a $45 part that needs $500 worth of labor to change. Some vehicles are more prone to them going bad than others it seems. Yours was probably clogged before it leaked so the new one had much better flow.
 

mindless1

Diamond Member
Aug 11, 2001
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Best way to attack this is make a list of all GM cars and year ranges in that generation, that "probably" use the exact same (or nearly so) core, dash, and engine bay arrangement, then watch some videos on youtube to see if there's anything beyond your willingness to do. Offhand I'd start with youtube searches for a Bonneville or Lesabre.
 

MtnMan

Diamond Member
Jul 27, 2004
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I used one from Autozone for my Ford with a lifetime warranty, thing is it's a $45 part that needs $500 worth of labor to change. Some vehicles are more prone to them going bad than others it seems. Yours was probably clogged before it leaked so the new one had much better flow.
I bought this truck new, and was never impressed with the heater. It kept me warm enough but not much more. On the other hand the A/C would freeze me out in hot weather
 

BUTCH1

Lifer
Jul 15, 2000
20,433
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Best way to attack this is make a list of all GM cars and year ranges in that generation, that "probably" use the exact same (or nearly so) core, dash, and engine bay arrangement, then watch some videos on youtube to see if there's anything beyond your willingness to do. Offhand I'd start with youtube searches for a Bonneville or Lesabre.
I always buy a Haynes or Chiltons manual for every vehicle I own, it's the best $10-15 you can spend. Although they are not inclusive you can get an idea of how difficult a particular job is. Heater cores always suck, but if you need an AC pump down/recharge then you will need to pay a shop for that before + after the install.
 

mindless1

Diamond Member
Aug 11, 2001
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1,789
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^ I used to buy the manuals but these days I find them of little usefulness beyond bolt torque specs. More often I get much better help watching a youtube video, reading topics in owner oriented forums, and drawing upon past experiences... sometimes you just need to figure out how much downtime is tolerable and whether you're going to need a special tool, then dive in.

Even if you need to pull the AC and recharge it, that's a constant either way to get the repair done in that specific vehicle, so still a matter of doing as much work yourself as possible... so long as it isn't something that if you get stuck, might require towing the vehicle due to being undriveable. There are mechanics you can call out to the site but meh, I've heard too many bad stories about going that route.

Granted, it may be *illegal* to pull your own AC and let it vent out. I've heard that some shops will evacuate it for free to get the recyclable refrigerant and others charge around $60 to $100.

I'm going off on a tangent though, it's not reasonable to talk too much about AC until (if) it is determined that the AC does need touched. It may not, particularly on a big old Park Avenue. Same for the dash, there might be enough room to work with the glovebox out.
 
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BUTCH1

Lifer
Jul 15, 2000
20,433
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Yea, a lot of the time I get great tips from user forums, for my Malibu it started getting "lost" trying to find which gear it needed to be in. At first I thought "*hit, tranny's going bad" but I checked the forums and found 2 other people had the same issue an it turns out the paddle-shifter wiring is too short and tends to break. Took off the console and yup, that was the problem, some quick soldering and all was fine, last week I heard a strange rattling from under the engine, checked the forum and again, found out several other people had the same problem, a broken heat shield mount. That being said a $12 manual can give you an idea if the job is tenable or not or if you have the proper tool's required to complete the job.