When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
Recently I have noticed my car running a little hotter. I wasn't too concerned at first, as it was 100 degrees. Today after driving an hour and a half on the interstate, it was running just a little hotter than normal. I found this to be a little more concerning, as it was only 75ish degrees and pouring rain. This really weird thing is that I was at the ATM for no more than 2 minutes and the temperature increased up to about half way on the gauge. As soon as I took off it went right back down. It did the same thing again at a red light. After letting it sit a while, it was fine. In the past few months I have let the car sit twice for about 5 days at a time. Upon my return both times, there was coolant on the floor. However, I never notice even a drop when I let it sit overnight. I cannot figure that out at all. My car has 113,000 miles. It's an 07 Type S. I had the water pump and thermostat, along with the timing belt, done at 98,000 miles. Any ideas what this could be?
Next time you see coolant under your car you should take note of where it's leaking from. It will point you in the right area where to look. You might even see it leaking. It's the best time to find the leak. If it's minor it will only leak if the cooling system is under pressure. So pop the hood and look.
A good point to start is with the new water pump, it happens, hoses, radiator, cap, etc.
Since you already have a leak. That means the car will overheat at a lower temperature due to lack of pressure. Also air will be entering the system which will cause hot spots.
Bottom line is get this fix asap. If it goes into the red you are flirting with catastrophe.
When it was leaking, it was a few inches to the left of the center of the front nose. Seemed to be right in line with the tire. So half way between the tire and center of the car!
The other day I looked under the car and noticed a puddle of coolant, and I noticed a lot had gone down the side of the transmission. It's so weird though, it doesn't do it all the time. I took it
to the mechanic immediately. I got there and it had all dried up and it wasn't leaking anymore. He put pressure on the radiator, but it wouldn't leak. I looked tonight and no puddle, but I did notice a little fluid around the top left of the battery under the two hoses. When I feel the hoses, it doesn't feel wet. Is it more than likely the hoses, or is there possibly another issue?
The pressure will be low in the cooling system if there is to much air in it so keep the system full as much as possible. That way you have a better chance of finding the leak.
Keep the engine bay dry so it's easier to detect any additional leakage. Use a dry rag or napkin and run it on the bottom side of the hoses and hose fittings to see if it's leaking from there or anywhere where you can't see behind.
Leaks can come in different forms. Some drip others may shoot like a water gun. In general the highest wet spot is where the leak is starting from unless it was sprayed.
I went and took the battery off to get a better look. I can't tell if it is coming for what I have the arrow pointed at in the picture? (What is that called??) Or if it running down from the thermostat house? There is one lite drop of something under the thermostat housing, but for the amount that has leaked, it seems a little too dry to me for it to be that. Opinions?
That looks like a trans presure control solenoid to me, no coolant in that, only ATF.
The current pic looks like coolant not ATF.
Your best bet is to top off the coolant and warm up the car then open the hood and wait for it to leak. It might help to have a second person rev the motor a little.
Oh dry off the coolant so the leak will make a freah trail.
You're over thinking things. Find the leak and address it accordingly.
The other poster didn't mean the thermostat is leaking. Thermostat do not cause leaks. What the other poster probably meant was... well I'm not sure what the other poster meant. The poster can answer that best.
If the leak was coming from the thermostat area it could be the thermostat gasket, hose, hose to water manifold, loose hose clamp, a crack in the water manifold or thermostat cover... etc. Something like that.
Cracks in water manifold or thermostat cover very rare.
As you can see there are many possibilities. That's why I said find the leak and address it accordingly. Don't guess.
I'm trying to remember, the Type S has the transmission cooler in the radiator and not the little heat exchanger on top of the trans like the rest do, right? If they do have the heat exchanger on top of the trans, I would look there first but I don't think they do.
Don't destroy the engine while you're trying to find the leak. The gauge is buffered meaning it takes a big temperature swing on either end (hot or cold) to get the gauge to move out of the normal area. Manufacturers started doing this because coolant temp is always fluctuating and by buffering the gauge it avoids customers bringing in the car unnecessarily. If it moves above normal, you need to take it seriously and do whatever you need to do to get it back down as quick as possible.
The fact that it cools off nearly instantly when it's revved above idle tells me the coolant level is low even if it's ok in the overflow reservoir. I bet your heater doesn't work at idle either, when the gauge starts to move into the hot end. The good thing is this eliminates pretty much everything from water pump to fans, to radiator efficiency.
Finding a leak is usually not that hard, especially once you know the general area. You might want to turn the heater on while looking around in the engine bay to see if the leak gets bad enough to spot. Since the thermostat was replaced, do as suggested and look around the thermostat but pay special attention to under the thermostat bolts. It's easy to miss a leak that travels through the bolt hole and comes out under the bolt head.
I'm lost as to the exact location of that picture but make sure the large bolt that goes through the hook does not go through into a water jacket and is leaking under the head.
I've seen all kinds of weird things, don't rule out anything. I've seen coolant coming out of wire harnesses. Check the wire harness above the coolant puddle. I've seen the coolant make it's way through a defective temperature sensor and the wire harness had a tight enough seal that the coolant made it's way through the sensor's wire's rubber jacket all the way to the ECU and fried it. That was frustrating, finding coolant in the ECU yet no source of coolant near the ECU. It can travel into places you wouldn't believe when under pressure but it's most likely the thermostat housing or one of the hoses that had to be removed when replacing the thermostat.
The other problem, and it's unlikely, is the cooler in the radiator has a leak and you're getting coolant into the transmission. This will mostly happen when the engine is turned off. The cooler circuit loses pressure while the cooling system remains under pressure for a while and forces coolant into the transmission. It will eventually get overfilled and puke out of the fill tube into the area pictured. I know that's not the case because it would be a mix of ATF and coolant but for peace of mind you might want to take a look at the dipstick. Very unlikely but it's easily eliminated as a possibility.
Have you cleaned it up, started it up, and watched to see where the leak is coming from yet?
The other day when I was with the mechanic we had to car on and it wouldn't leak, so it seems the car being on does no make it leak. I had my sister feel behind the thermostat and she was a water looking fluid on her fingers, so I'm assuming that would be it!
Clean up the engine bay the best you can, check coolant level when engine is cold, it has to be at least past min level on the overflow tank. Start and let engine idle for 10 to 15 min till fan kicks in.(No A/C, turn it off). Turn engine off and see where it leaks, paying attention to thermostat housing and where the head gasket is. I'm assuming there's no sweet smell or white smoke coming from the exhaust when you first start it up.
I ended up having the thermostat and gasket. It fixed the issue, or so I thought it did. It didn't leak for 3 weeks, I'm guessing. Well, yesterday I noticed when I turn the car of the fan was still running, and it was not terribly hot. Today I went somewhere and was about to turn the car off when I saw the gauge going up steadily, so I immediately shut it off. I checked the coolant, and it was not full like it should have been. I had some still with me, so I filled it up. Got back to campus and let it sit for a while. I went back to look and I have coolant again in the exact same spot (s) as before. Could it possibly just be the housing itself? It so weird how it stopped and then occurred again. I know this sounds weird, but I wonder if the housing has been bad the whole time, but when they took it off and put it back on, it helped it for the time being. Any thoughts? I'm 5 hours from home now, so it sucks not having a mechanic I know about. Anybody know where I can take it in the Knoxville area?
Yes, it is leaking. On top on the transmission there is some coolant. Exactly where ithe was last time. It feels completely dry under all of the hoses. It's just 6 inches right of the thermostat and it seems the is a slight down slope from the thermostat to where it is resting. I don't know anything else it could be. Also, I replaced the radiator cap under 2 months ago.
I went back out to the car and there is something moist around the housing. Would this indicate it is the housing, or would it indicate it is the water passage? I talked to the dealer, and I know the water passage is like $190. Should I replace the water passage, or just go with the cheap option and replace the housing to see if that fixes it?
Before you buy anything you need to know exactly where the leak is coming from. You need to clean away the coolant that is already there so you can pinpoint where it is coming from.
Use a mirror and flashlight if need be until you can find out where it is coming from. Remember, coolant cant leak upwards so find the highest area where it is wet (assuming it is not spraying).
It is very unlikely that the thermostat housing or the water passage itself is bad. It could be the gasket like what happened to me, or a hose ect.
Before you buy anything you need to know exactly where the leak is coming from. You need to clean away the coolant that is already there so you can pinpoint where it is coming from.
Use a mirror and flashlight if need be until you can find out where it is coming from. Remember, coolant cant leak upwards so find the highest area where it is wet (assuming it is not spraying).
It is very unlikely that the thermostat housing or the water passage itself is bad. It could be the gasket like what happened to me, or a hose ect.
Hope this helps.
I just went back outside to the car and I ran my finger around the seal of thermostat housing. The was a moist substance on my finger, so I would assume this is where the leak is coming from. It has to be coming from that area. There is nothing to the left of the thermostat housing, which I believe is a little more elevated. The coolant is not resting right below the thermostat because there is a slight slope downward to the right about 3 or 4 inches that it is going down and it sits there. Like I said before, I have already replaced the thermostat along with the gasket in July. Therefore, it would have the be the housing, a faulty gasket, or the water passage. Correct? It's really difficult for the mechanics to diagnose it because it will only leak when it is sitting for a while. If it does leak while I drive, the heat just causes it to evaporate. If I drive the car to the mechanic after letting is sit all night, what had accumulated the night before will just dry up while driving.
Just because you replaced the thermostat and gasket (although its not a gasket but a seal) doesn't mean that it has to be from the housing itself (although it may be). The likely hood of the housing itself to fail is very small, what is more likely is that the seal for the thermostat either failed or is not seated properly. I would replace the seal and see if that fixes it and while your at it, inspect the housing to see if there are any cracks or anything.
All of this assuming that this is indeed where the leak is coming from based on your findings.
If you can't find the leak then change both gaskets. The water passage gaskets and the thermostat gasket again. Examine the parts while they're are off the car and you might want to change some of the hoses while you're at it.
If you can't find the leak then change both gaskets. The water passage gaskets and the thermostat gasket again. Examine the parts while they're are off the car and you might want to change some of the hoses while you're at it.
What is the difference in the water pump and water passage? Are you just saying change the gaskets, not the passage itself? How much labor should that require?
07-03-2015, 10:14 PM
