1998 S70 is going through coolant like crazy

[DatVolvoChick]

Forgive me this might be long but I want to be very thorough when describing the issues of my car and what's going on. Please try to be patient with me as I'm not very mechanically inclined, so I might not know some technical terms like you guys do. Thanks!

So on 7/2 I was driving home down a two lane road, and I encountered someone going 45, speed limit is 55 I tend to go between 60 - 65. As I attempted to pass this person instead of slowing down they decided to speed up, causing me to speed up (Pushing my gas pedal all the way down) and I finally cleared them and I was on my way, I noted my coolant light turned on, but I thought nothing of it and I monitored the temp gauge the rest of the way home, the needle didn't move, I figured I would let it sit and fill the reservoir back up the next morning, I sometimes have to fill the reservoir up about once a month, it's never been an issue. I've gone through almost 2 gallons of coolant between the morning of 7/3 and today, I'm actually about to empty out the second gallon of coolant.

What I've checked so far:
My oil is not milky, it is not too thick. It is the right consistancy and has a pretty golden brown color.
I do not have white smoke coming out of my exhaust or under the hood (To my knowledge, I am currently at work and will double check this on my way home / when I get home)
The coolant only gets out of the system when the car is actually being driven. If it's idling in the drive, or just sitting in the drive, the fluid does not get deminished. I can fill it up and leave it for hours and it will be the same level when I get back.
We cannot find any kind of leak anywhere under the bonnet or other wise. When I pull out of parking spaces or out of the yard there is nothing under my car.

sidenote:
Since I purchased this car in may 2013, I've had this thing with the heat. Like when I turn it on the air smells like maple syrup. I've been told something to do with my heating core, but I'm not entirely sure if this is where the extreme loss of coolant is coming from, as the floorboard by the driver and passenger is never moist / wet after I've driven it. I've placed down a white cloth on the passenger side floor to see if anything comes out when I actually drive home and I'll feel around when I get home too.

I keep being told this is a cracked headgasket, I really hope they are wrong because I cannot afford a cracked head gasket, period.

Any ideas? I really need help here, I don't know what to do.

[dosbricks]

Welcome to the forum. Anytime you are loosing coolant it's an issue that needs to be dealt with because sometime or other it's going to grow worse and could lead to engine overheating and the premature demise of a good car.

That sweet smell from the heat ducts is a sure sign of a leaking heater core which is located under the dash ahead of the center console. You could start by pulling back the carpet next to the front of the console and see if coolant is soaking the padding under the carpet. That's a big space on both sides and can absorb a lot. You may have another small leak in the engine bay where hot coolant is vaporized as it comes out rather than dripping on the ground. Do a thorough inspection everywhere the coolant is routed. Let us know what you find.

[DatVolvoChick]

I just went out to my car and pulled some of the carpet back, and it felt kind of moist but it's been about 6 hours since I drove it in to work, when I get home I'll check it as soon as I get there for moisture. Would this be on both sides of the console?

For the thorough inspection of the coolant routes, does that require the car to be up on a lift? or is it possible to do that with it on the ground?

Also, what are the chances of this being a cracked head gasket? I don't have the symptoms so I don't know why I keep getting that response, my car hasn't over heated so I don't understand how the head coulda cracked when it's never overheated.

I appreciate your patience and your help I really do

[abscate]

If it hasn't overheated ever it probably isn't a head gasket or cracked head. Good news.

You can have over a gallon of coolant stuck under the carpet in these cars and not get wet carpet - there is a thick underlay under the carpet and lots of space under the underlay. Your leaking heater core is certainly the place to start - replacement is about 100 USD and a DIY job.

Take off the footwell pieces and look for seepage in the core - its sits at about shin level above the tunnel. If the car has been running, it will be hot - very hot, so be careful. You will probably smell that same smell there if it is leaking, but stronger.

Coolant is really bad for small animals so be careful around pets - they will drink up the sweet taste and 50-100 mL will kill them.

[DatVolvoChick]

You were right I pulled back my carpet and there was coolant there. Don't really have time to repair the heating core until Saturday / Sunday so I got some sealant to put in for now to see if it'll work. I just need it to work til Saturday then I can actually fix it. Thanks for your help c:

[mecheng]

Sealant isn't very good for your cooling system it can clog cooling ports, once you replace it try to flush the system

[j-dawg]

it's summer; you should be able to bypass the heater core without too much effort until you have the time to get proper replacement parts.

see: https://www.matthewsvolvosite.com/forums ... =1&t=36651

[E Showell]

The maple syrup smell is a dead giveaway of a heater core leak. It is not that bad a DIY job. There are instructions on this site. It is a messy job, but not an overly complicated one. I know, 'cause I've done it. If you can operate a screwdriver, you can do a heater core replacement.

[abscate]

Sealant is bad. Return it if you can. Do some volunteer work for karma points if you have already put it in. Clogging and overheating one of these motors costs about 2000 usd

[rspi]