Tip & How-To about 1993 Subaru Loyale

I Smell Antifreeze when I start (drive) my car (usually when heater-a/c is on)

Do you smell antifreeze when you start your car? While it's running, driving - whether you smell it when your heater or a/c is on or not, if you smell it, then you have a leak. The first thing to do, is open the hood, check the water level in the radiator. If it's full, your leak at this point is probably small, but small leaks can quickly turn into a large leak - which could happen wether your driving or while your car is parked, and off. When a hose leaks, it's because the hose has not been replaced for some time - and the antifreeze (and hot water, in addition to the hot/cold affect) eats/corrodes the inside of the hose - think of it like pot-holes, the weight of cars, weather, hot and cold, rain - "pivots" the pavement, asfalt, concrete, blacktop - what have you - and these small pivots, over time, with wear and affects of weather gradually become bigger. As the concrete (material, rubber hose) become pounded by pressure, frictions, heat, cold, etc - it, like all things wear out, weaken, and eventually give out.
So..."How do I find my leak, and how do I fix it?"
1. To find the leak, the best way is this. Depending on how long you've owned your car and performed your own maintenance, or had maintenance performed on your car; the best way is to replace all water hoses. On most vehicles (some are different, see your engine for details) there are four hoses. 1. Top radiator hose, which usually runs from the top of the radiator to the thermostat housing (mounted on the top of the block (sometimes the side, depending on make, model and engine size etc). 2. Lower or Bottom radiator hose, which usually runs from the bottom of the radiator to the water pump (usually mounted on the front (rear wheel drive) of the engine just behind the mechanical fan (some new cars have only electric, so in this case will be mounted on the center front most belt pully (usually pretty obvisous, unless it's internal, as that of subaru's). If you have a front wheel drive (and possibly all wheel drive) vehicle, your engine (most likely a four or six cylinder) is mounted "sideways". "How do I know if it's "sideways" ?" If your engine is sideways, one you have front wheel, or all wheel drive - your belts will be located on the (most commonly) passenger side of the vehicle, which puts your trasmission on the driver side. These water pumps are bit harder to get to, and is easier (and recommended to do so) to get to by lifting the engine out. If you have no means of doing this, consider a friend or relative with the means of this, or a certified technician or mechanic.
There are two more hoses that could be leaking, as well as one other part. First, the hoses, which include two "heater core" hoses. These hoses generally run from the back of the engine, into metal lines or tubes; (follow them from the rear firewall) to the rear firewall. These are what make your heater air hot. If you have a noticed a decrease in temperature on the highest setting with your heater, any one of these four hoses could have a leak. Inspect each one carefully, clean them if necessary (wipe down with rag). Also, by looking around the engine compartment for the green antifreeze fluid, you can more accurately determine the location of the leak. If you have a puddle, directly under the front part of the engine (bottom center area as well due to gravity) when the car is parked, it could be 1. water pump (do not drive car until fixed) 2. thermostat housing, replace gasket and thermostat. 3. top or bottom radiator hose, leaking near or at the radiator, water pump.
"Where do I start, and what do you suggest?"
1. Regardless of where the leak is, and regardless of where you have found the leak, from experience as I do ALL external (some internal) repairs on my vehicles, below is what I suggest to do if you smell antifreeze, and suspect, or have located a leak.
1. First, repalce ALL hoses. They include (for reference at parts store)a. top radiator hose and clampsb. bottom/lower radiator hose and clampsc. heater core hoses and clamps
2. When performing this repair, it is necessary to drain the radiatior (and block if possible) of as much fluid as possible into a safe container (inquire with parts dealer about disposal options of fluid).
3. Thermostat - replace thermostat and thermostat gasket (when purchasing this, open the box, or ask the store rep if it comes with the gasket as some (most) do not). It is imperative to replace this gasket. DO NOT use silicone or "gasket maker" except for in emergency (side of the road break down) instances, or if you do not have the funds, and are equipped with this, and need it to "get by".
3. Once you have replaced all hoses, thermostat and gasket, and have refilled the radiator (put antifreeze in first, then top off with water); ensure the water level is full - and inspect for any leaks. If there are any leaks. (also make sure to dry any pools, or small puddles of water that may have accumulated on the block as a result of a possible thermostat leak), so that when you start then engine, if there is still a leak in this area, it will be better determined by the current fluid, and will not be assumed as a leak from the start. If not leaks, sit in the car and turn the heater up full blast. Alternate the settings between vent, defrost, floor etc, ensuring that consistant heat (same temp, not fluctuations, or cold air) is being disbursed.
If in the event you have replaced all of the above, there are not leaks for any hoses, thermostat housing, heater core, or water pump, and you are still losing water, or the heater is not producing hot air, there are two options left that will cause this.
1. The heater core is plugged - which in this case could (and most likely) explains the leak (wherever it is/was). In this case, you can buy a new heater core, but these can be prettty spendy. Instead, first remove the heater core (and yes, you'll have to drain the fluid again...however if you drain it into a clean tub (or what have you) you can reuse it. Next, if you have an air compressor or other means for pressurizing the heater core, you can "flush" it out, clearing the blockage. You will know when you've cleared it, when you have water (or air) blowing in from one end, and feel it out the other. If you use air, be sure to run as much clean water through it as well to ensure proper flow. If you cannot successfully clear the blackage, locate a parts yard (scrap yard) and purchase a used heater core. Perform the same flush operation before installing - chances are if you just run water through it, you'll be good to go. Install, refill system with drained fluid, adding water as needed (as most will be in the block). Start the vehicle, and check the heater temp again. Hot Air now? GOOD!! No hot air? Ok, if you do not have hot air still, and I know this seems endless at this point, but I assure you there are only two options left at this point. 1. heater electical system (fuse, relay, or the heater switch box itself) check all fuses, and relays, however if your heater works, (blows, these are good, and have not affect on the temperature itself) which leave us with 2. water pump.
Please note, that in most instances of heat loss, just because the leak is elsewhere, does not guarantee the water pump is still good. It may still be "working" but when leak is *******, then the water pump is not doing it's job, which means it's circulating more air than water, of which it was not designed to do. So, what happens is the bearing that the "fan" or "blades" are riding on (help turn smoothly), get hot, weak, and eventually wear down, start rolling over eachother, breaking and eventually will cause the pump to sieze, (sometimes "welding" the blade to the pump itself. This causes no flow at all, which in turn creates an even bigger leak, and in a lot of instances, at the bottom of the water pump (due to gravity). Water, like air, will pass through the path of least resistance. An engine is more likely to have a leak on a gasket then a hose, as the gasket is smaller, thinner, and weaker.
At this point, to really inpect the water pump, it must come out, and if the water pump is not "noisy", and you'll hear if if it's bad while engine is running....then it's most likely good. However, I suggest replacing it anyway, and for most vehicles they are fairly cheap (I do not recommend re-furbished for this part, however it is a "cost affective" alternative; of which I've had to do).
So...lets review (under assumption): and consider the very last option if all else have failed to correct the leak.
1. We have replaced all four hoses and clamps2. We have replalced the thermostat, and gasket3. We have (possibly) replaced or successfully flushed the heater core.4. And we have no inspected (and possibly) replaced the water pump.
So, this has all been done...if there is still a leak, and you have not found it - your heater is still not producing hot air as desired (strictly cold air) then the only thing left is a blown head gasket. If you are mechanical, have the tools, and a repair manual (or experience), you can do this yourself; however - I recommend having a certified technician or mechanic perform this repair as they have all the "right" tools for it, it requires removal of the valve cover (will need new gaskets for that/those) and is a bit more a hassle. Not too complicated, just time consuming to the novice "home" mechanic; and the work can (by most repair shops) be warrantied,.
If you have any questions about this tip, or the information about it, suggestions, additions, or editing tips, please let me know. I can be e-mailed directly at isaachayes2008@live.com.
Thank you for choosing Fixya.com for your automotive questions and concerns, and thank you for reading my tip(s). Please view other useful tips I've posted as well.

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smell antifreeze heater and defrost

Broken heater core. Keep an eye on your antifreeze level

Jan 31, 2014 | 1996 Honda Accord

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Not Overheating, Smells like really hot antifreeze after I drive, a/c ok heater heats but when stopped air gets cold...stummped..thermostat?, Leak?

check your hoses and make sure its not getting low because when it gets low the hoses can get hot enough to expand and spit out antifreeze without overheating

May 18, 2013 | 2008 Chevrolet Impala

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sugary burning smell while driving

That smell is most likely antifreeze. If the smell gets noticeably stronger when you turn on the AC/Heater, it is possible that your "heater coil" has started leaking. You will need the services of a professional if that is the case. Those are very hard to change.

Another possibility is your thermostat is not opening, causing your engine to overheat - steaming some of the coolant (antifreeze)/water mixture out of the system.

And thirdly, it is possible that someone spilled antifreeze on the radiator etc when adding fresh antifreeze - and you smell it after the engine warms up. If your car is not over-heating and you are not having to ad antifreeze/water to the radiator, then just keep driving. The problem will most likely go away.

I hope this is helpful to you. If yes, please take a sec to rate me. Thanks!

Apr 04, 2012 | 2000 Chevrolet Impala

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either its the heater core or the thermostat

your heater core is definitley leaking and your blower is pushing the vapor into the cabin. It will only get worse. You can minimize the smell by not running your heater or defroster, but you wont prevent the coolant from leaking and potentially getting worse. Sorry to say, the core will need pulled and repaired or replaced. Sometimes stop leak additives will solve the problem if its not too severe. I have never been a fan of them, its only a band aid in my view. also if u got pets afoid leeting they smell the antifreeze very toxic can kill pets easily. hope this helps. rate above 4* cheers

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yes its your heater core. it went bad and needs to be replaced. it is housed underneath the dash

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