Spirit

I read a few threads on potential leaks - brake fluid and transmission fluid. I picked up technical bulletin SB 06-10-5. I've got a manual V6 Pony Package, 2006 Mustang. I'm at the stage of asking myself what this spot on my driveway is being caused by. I had noticed a while back in April a spot under the car. I checked it out for a few days, verified the fluid levels (per my manual), but nothing out of the ordinary. Not until yesterday (July 14), a spot of about 10 to 12 inches which was a little oily (though could be the asphalt blending in with the fluid). In early June, I took the car in for my first service check, nothing anomolous was found. Some questions for you (keep in mind, I'm not super mechanic inclined):

1. When you observed a leak, did you observe any fluid on the surface under your car, i.e. the driveway, asphalt?

2. Where is the output of the air conditioning located? (I suspect it is below the dash of the car on the passenger side)

3. What were the characteristics of the leaks you observed? Oily, clear, thin, thick? Does it remain as a stain on the driveway or does it dry up quickly? (In my case, I saw the spot yesterday evening, this morning, it's still there, there is an oily nature to it, it doesn't seem to discolor the asphalt, just darkens it because it is wet, I think it is clear).

The location of the spot is on the passenger side. I am not noticing any wierd driving conditions. I don't use A/C often, when I do, I see fluid dripping when the car is parked (which is normal).

Any thoughts would be appreciated.

Spirit

Just to follow up. I checked the fluid levels. Looked all fine. I did find one difference from the last time I checked the coolant fluid (yellow). It is near the lower level of the "COLD FILL RANGE", where it used to be in the middle (back in April).

I opened the reservoir, and noted that there was some liquid around the cap and dried up residue along the outside of the reservoir.

The pressure relief valve must have been exercised. The weather recently is very hot (still today). That combined with use of the car, the coolant could have been very hot, enough to trigger the pressure relief valve on the reservoir cap.

Just wondering, anyone out there have seen this before, how about those in hot climates like Arizona, Texas, Florida? (Temperature, last few days was over 30 deg Celsius, 86 F). Come to think of it, in April, there was a peak up to that temperature as well.

Any advice or hints would be helpful. Thanks.

stangster

Since everything else seems normal, it sounds like the fluid you found is from your AC. Next time you drive it and use the air, look underneath after you park. You'll probably see water dripping on the passenger side near the firewall.

theedge67

If it has an oily nature to it, it would not be condensation from the A/C. That would be pure water, pulled from the humidity in the air when it is cooled. If it is not colored (or you can't tell a color) then it is probably not motor oil or transmission fluid (for an auto). Brake fluid is likely out as well, because the resevoir is on the driver side of the car, and it is usually red. The liquid is probably coolant, (antifreeze) especially since you noticed that the level is a little lower than it was previously. Coolant is slightly oily, as it lubricates the water pump and keeps the system from corroding.

Regardless of the outside temperature, there should be no reason that the relief valve opens up and dumps coolant on your new mustang. If the cooling system is functioning properly, it has more than enough cooling power to keep the engine at the proper temperature, even with the A/C running and 110F outside. I suggest taking it to the dealer and explaining the situation, and have them check the cap for coolant leaks. Just my $.02

Spirit

Thanks for the inputs. I decided to take some pictures.

An update. I didn't take the Pony out this weekend (just happens that way). When I got back from work, while the engine was hot, I opened up the hood (just wanted to see what things looked like when hot and if I would be witness to a leak). I did see the coolant level higher than the max "Cold Fill Range", which I took as normal as this liquid is quite hot and would expand. Of course, I didn't touch the cap, nor open it - sizzle. The fluid level was above the top of the clear reservoir.

I ate dinner, came back out, the level was now between the two lines of the "Cool Fill Range". Engine was still medium to hot. It is then that I took the pictures.

The pictures definitely show there is something happening at the cap location.

Anyone else observe something similar? Take a look under your hood. I will take these photos to my dealer.

Spirit

Thanks. Your explanation sounds logical. I checked out the temperature gage while driving, and looks like the cooling system is working, in between C and H, right in the middle. I'm just wondering a few things including performance of the fluid or if the temperature sensor is reading the right temperature. Looks like I'll go to the dealer. See pics in my previous post. Should be convincing on where the spot came from.

I'm wondering if this is normal for '06 or '05.

Roush6car

The same thing happened to my 06' GT back in spring , at the time I had my MGW cap on. We had it pressure tested & it was fine but it never seemed to screw down correct on the tank , so I switched back to the stock cap. It hasn't happened again since knock on wood. The day it happened was after a 2 hour run with the last couple miles being stop in go traffic. Weather was sunny & low 80's. I had just parked the car and was walking away from it when my wife noticed liquid running out from the engine bay. When I popped the hood , just like your photos mine had "burped" over at the cap. No rhime or reason to date.....please keep me posted! Thanks , Erick

theedge67

From what I've gathered in other posts on this website, the temperature gauge is basically useless, along with the oil press. and amp meter. They are "dummy" gauges. If you'll notice, pretty much no matter what kind of driving or outside temps, the gauge doesn't budge once it gets up to temperature. I've read other people posting that when they install an aftermarket temp. gauge it shows the actual temperature fluxuates greatly depending on the kind of driving and outside temp.

What I'm saying is basically this: even though your temp gauge shows normal, I wouldn't trust it to tell you that your car is not running hotter than normal.

Have your dealer check it out and see if the cap is faulty or your car is running too hot.

Spirit

I made an appointment to see the dealer this Friday.

Roush6car: When I observed my little burp, it was after a 20-30 minute drive along a road full of stop lights (so, stop and go), and it was hot out. What is with wives? They notice everything, my wife pointed out the spot on the driveway. Somewhere down deep, they're looking out for us.

I thought this car was hot... maybe too hot.

I'll keep you posted on what the dealer says.

Spirit

I checked out the post on water temp:
http://forums.bradbarnett.net/showthread.php?t=50339

Interesting answer to your question. The gauge is not too useful. I may look into getting an independent temperature gauge.

dprestia

Take a piece of white cardboard or paper and place it where she drips. Now you know the color and thickness.

Hada69

I noticed an "oil" spot under the car the size of a half dollar. My car sits for extended periods in the garage. (1350 miles in 17 months). When I jacked it up, there was red oil dripping from what I think is the transmission line. The point at which this line went from a metal tubing to a rubber tubing was leaking. The clamp squeezing the rubber to the metal was not far enough onto the metal tubing.

theedge67

Yes, I've been wanting to get something that actually works myself. I would really rather leave the stock appearance though, and not have any aftermarket gauges cluttering the interior of my car. I'm trying to investigate whether a different sender unit attached to the gauge would work, and if so if it would screw with the computer or turn on warning lights. Seems like it wouldn't be too hard for someone to make an aftermarket sender unit that would directly bolt on. I'd pay some $$ for a stock fully functional water/oil gauge.

KdF

+1

Bring `em on

Spirit

Went to the dealer this morning. Asking me some standard questions on the dried up residue: did you fill up the reservoir recently? (and thinking, did you spill any?). Replied, not, haven't touched anything under the hood since getting the car in January.

They pressure tested for leaks, none found. Suspecting a faulty seal in the cap, the replaced the reservoir cap. They cleaned up the dry residue, looks like new.

I recorded the fluid level, and I now have a clean reservoir. For a few weeks, I'll observe what happens.

Spirit

I went to the dealer at the end of September. I noticed the reservoir tank had the same dried up residue as my first observation (and this after the dealer cleaned the reservoir back in July. On my second visit, the dealer changed out the cap, again (and this after the dealer performs some standard checks) - By the way, does anyone know what they do in terms of a pressure check, what kind of set up they use, etc.? (my dealer won't let me be by my car when they're working on, which I can respect due to security/safety, and not having someone breathe down their backs).

Not completely satisfied the dealer solved the problem permanently, I went to an independent mechanic (he takes care of my other cars). I explain the problem, he asks me to keep the car running, make the fan comes on by itself. He then unscrewed the cap, looked at the gasket in the cap and noted that the gasket was likely not making a complete seal. Photo attached. (Note: the drops of water are there because it was raining when I took the picture).

The red arrows point to the indentation caused by the lip of the reservoir on the gasket. Note the red circled area shows no lip, likely due to the gasket not lying or compressed against the reservoir.

Is this normal? What's under your coolant reservoir cap? If you can post photos that would be really appreciated, I can compare with.

The independent mechanic is suggesting the reservoir opening is not flat with respect to the threading.

Next step: take the car to another Ford dealer, get a written assessment of this observation and return to my original dealer to do something about it (I'm not too happy that they're not addressing the root problem).

Any opinions?

pebkac

When I went for my replacement cap they used pressure tester that the cap screwed on to and then they pump it up like you would a bicycle pump. The tester has a fitting that adapts to the cap and they also have one that makes it a cap. He tested the cap before I was by the car and he came to get me when he was testing the radiator and the rest of the system. I will have to check my cap for the indentation like yours. I suspect mine will be fine though.

Spirit

Thanks for the information.

Interesting. This helps explain things (though no conclusions yet). Let's say the problem is with the reservoir opening not being even as I am suspecting. Pressure testing the cap would not help assuming the test equipment fits securely to the cap. Pressure testing the reservoir would not help assuming the test equipment fits securely to the reservoir despite an unevenness (the test equipment gasket or other sealant likely compensates for the unevenness). I am assuming the test equipment interface to the cap and to the reservoir is a lot more robust and different in design than the interface between the cap and the reservoir.

But there is no test that tests the cap and the reservoir together.

That's the path I am on for now until it can be disproven with evidence.

If you can post a picture of your cap's gasket, that would help me see either a good fit (to compare against) or something similar to mine.

pebkac

I didn't have my camera yesterday otherwise I would have. Have it today and here you go. I have the cap with the seal and 2 of my bottle. Look and see if your bottle has the extra lip that is making the impression all the way around. Could some of it be missing on yours?

Spirit

Deciding this was not very critical knowing that the cap was not fully seating to the reservoir, I waited a few months before taking action. I went to a different Ford dealer to confirm the problem. I took the photos I posted to this forum. I won't go into the rather hard time I had with customer service to have a technician look at this given there was no leak observed after the 2nd cap replacement, and ensuring the wording in the service contract was exact, i.e. I would have to pay $29.95 if there was no leak found vs I would have to pay $29.95 if there was no defect in the cap or the reservoir. Honestly, there was no leak (enough of the liquid burped out that the chances of any more burping out was very small, and I have not observed a leak since September), but that does not mean the problem was solved. I pushed for the second set of words on the service contract.

In the end, the technician indicated the cap did not seat properly on the reservoir. The reservoir was changed out. I won't be able to follow-up on this until Spring, my car is in storage now for the winter.

Not sure what service was like in the 1960's (I can only imagine it was very good and courteous), but when Ford decided to model the 2005+ Mustang after the 60's model, the service should have been modeled like service back in the 60's. (There are still 60's mustangs out there, there must be a reason for that).

Thanks to TMS'ers for their help and photos. Excellent support.