Smell of Coolant after long, steep hill decline

The coolant is pink in the prius, there are 2 coolant reservoirs also, one is for the engine, and the other is for the is for the inverter. I believe they both take the same type of coolant. The reservoir closest to the radiator is the one for the engine and also for the cabin heater. In any case both have a line on them marked I think they are labeled as the common Max cold.

I would think that one of 4 things happened. 2 of them good or normal and the 3rd and 4th not so good.
1. you were going down the hill and the engine opened up the thermostat and the pressure in the system vented a little of it and you smelled the residue. (normal) (sometimes it splashes on the bottom of the engine or exhaust)
2. Possibly the pressure loosened up the cap to the reservoir and a little bit steamed out. (re-tighten not a big problem as long as you didn't lose too much)
3. A sharp object managed to go through your grill and put a small hole in your radiator. (not so good)
4. Another possibility is that a hose is leaking. (not good) but easy to fix, if you can find it.

The easiest way to find out if your car does have a leak in the cooling system is to put a large flat piece of cardboard under it especially after a long drive. And leave it set under it for a few hours or overnight.

 

<div class='quotetop'>QUOTE(SoopahMan @ Nov 27 2007, 03:14 PM) [snapback]544879[/snapback]</div>

I have nothing productive to add so stop reading now. But I would like to point out that there's several on this forum that commented about how having a temperature gauge is not needed in a Prius because the Prius is so advanced you never have to worry about it overheating. This moment would be a good time to have such a gauge. The smell of coolant combined with a sporadic gauge can easily help determine if you're having a problem. A sporadic gauge usually means your thermostat is going out or you somehow sucked air in to the system (through a hole somewhere).

Anyway, I don't know offf hand what color the Prius' coolant is, but that sounds like the coolant overflow as extended life coolant is all sorts of colors (other than green). If it is low I'd say you either have a leak (do you have any drops on the ground... usually coming from the wheep hole or possibly from a hose itself)? If not you could have a thermostat going out and your coolant is starting to boil before the thermostat opens to start flowing coolant.... oh, and a radiator cap going out can also cause this. The radiator cap's job is to keep in a certain pressure and if that pressure is exceeded it will allow the coolant to overflow. If the cap can't keep pressure your coolant will boil at a lower pressure.

If you're unable to determine which bottle is the coolant bottle you're probably not going to be able to diagnose the problem yourself... sounds like it's time to make a trip to the dealer (or trusted mechanic).

MIke

 

<div class='quotetop'>QUOTE(SoopahMan @ Nov 27 2007, 07:17 PM) [snapback]544938[/snapback]</div>

There is no danger with taking off the cap with it cold, other than making sure its tight when putting it back on. Although remember that if you loosen it while the car is in READY (engine already hot) even if the ICE isn't spinning after the thermostat opens up it most likely will spray because of the pressure and possibly burn you.

As far as Gliding the engine would cool while gliding (under 40MPH) naturally by air, but would most likely still overheat while pulsing without any coolant. If you are on an Electric Glide (over 40MPH) the engine although not burning gasoline would still generate heat due to friction as it spins at 41MPH and over regardless. Not to mention the heat that the Inverter would generate in that scenario. Make sure you check both reservoirs, as I am pretty sure they are seperate systems. I still say that most likely is that the system let out a little coolant due to high pressure, and most likely just splashed onto something hot like the exhaust and probably is nothing to worry about. But you are doing the right thing and checking it out.

 

<div class='quotetop'>QUOTE(SoopahMan @ Nov 27 2007, 07:17 PM) [snapback]544938[/snapback]</div>

As in any car ever made the coolant system is a closed pressurized system. There is no scenario where you will smell coolant in the interior unless you have a leak...or have overheated the car so badly the coolant is steaming out. I do not think you have overheated yet as it would throw a CEL or other alert. But if you smell coolant anywhere in or around this car or any other car you own you have a leak. Period. Your nose is the best tool in the toolbox for this issue. This car has no user temp gauge and I would imagine like most sensors by the time it alerts you to a overheat much damage has ensued. Take the car to the dealer asap. They will do a pressure test on the system and find the leak.

 

Look for hints of light pink crusty dried droplets anywhere you
can see underhood. One place I get a tiny bit of seepage is
apparently the water pump seal, and the pulley then flings a fairly
sharp line of splash across the radiator hose, air intake, and
a little bit on the underside of the hood. I smell *that* on long
uphills [during, not afterward] sometimes, but the leakage rate
does't seem to pull the reservoir level down at all [I've topped it
up a tiny dribble's worth maybe once the whole time I've had the
car], and there doesn't seem to be anything wrong with the water
pump. So check your reservoir level and if it's not going down
appreciably fast, worry not.
.
_H*

 

By the way, your post makes it sound as if you spend a lot of time driving in "B". One should not normally drive in "B" (unless maybe one drives in the hollers in Kentucky). "B" should be used only to avoid riding the brake pedal on a long downgrade. It cannot damage anything, but in normal driving it will reduce your fuel economy.

 

45 degree hill!?! That's at the limit of what a good 4wd can negotiate. Are you sure it's really 45 degrees?

Tom

 

If you see no leaks of any sort and have not smelled anything funny since, it may merely have been the odor of relatively new electronics getting hot for the first time. That is nothing to worry about.

You can shift to "B" at any speed without harming the car.

 

I've got the mystery coolant smell too. I've looked around but haven't found any leaks. The coolant level hasn't budged so it must be a really small leak. I live at the top of a hill so the car uses the engine heavily coming home, which is when I often smell coolant. Any particularly infamous leakage points on the prius that take a little digging to find?

 

I would say that coolant leakage generally is not a big problem with Prius. However if you can smell antifreeze and don't see an obvious leak, the first area to suspect would be the cabin heater core.

Since your car is pretty new it hopefully is still covered by the 3 year / 36K mile warranty. If the smell is strong enough so that you can point it out to your dealer's service writer, it would be quite reasonable to report the problem.