Sneaky Coolant Leak Fixed
 

I am not good at video-ing while fixing things so this post is the best I can do. I own a 2006 GT Convertible automatic. I've only had it about 5 months, it has been a real problem child. Anyway, I found myself on the side of the road not long after buying the car, it just lost all power while going down the road, the motor just let off and I coasted to the side of the road. It was strange, it would idle fine (actually sounded good) but had no power when I put it into gear. Got it towed home... trying to figure it out I read that there are some nice sensors built into the heads that will shut down some of the cylinders if it overheats. I went, "uh, overheats?". Looked at the coolant overflow, completely empty. <<<puzzled looks>>>. Bought 2 gallons of the preferred coolant that I looked up online, thinking I'll keep a gallon around just in case. Oh, btw, I've never seen a damn drip or leak anywhere, this is what puzzled me greatly. Anyway, after putting both gallons into the car and it was still slightly low, I'm really baffled.... until one day I was toying with the car and took it for a spin around the block. I kinda horsed it, I ripped it around a corner or two, just feeling that 300hp 4.6. When I get back into the driveway, I notice a leak!!! Yes, it is coolant, but it is on the passenger side about the middle of the car... more puzzling looks - how the hell would coolant be way back there dripping?
So, to shorten the story, I did some looking and thought I found the culprit, and ultimately did. Under the intake manifold there is a coolant line that uses an elbow and a factory-crimped hose. I found a good video about this, although there wasn't much about it (hence my reasoning for this post). I spent my last Saturday taking the intake manifold and alternator off and sure enough, it looked like whomever had the car before me had squirrels or something living under the intake manifold... there were acorns, wood chips, all kinds of crap under there, along with a dripping elbow and hose. What was happening was it wasn't leaking that much at a time, and this rats nest was holding it in while sitting, but apparently dripping on the road while moving. When I ripped it around the block some of the coolant forced its way past all the crap in there, and voila, revealing the leak. Anyway, a $15 elbow, a couple of hose clamps and less than 6 inches of hose fixed the problem. Of course, i cleaned the living heck out of the top of my block down there, put new gaskets on the intake manifold, and so far, the problem is fixed. I've driven it twice and when I shine a light into the crevices I see a nice, dry hose/elbow and a dry cavity down there.
I think it is a very poor design but thought i would let anyone who owns a 4.6 and has a puzzling anti-freeze leak, this is probably your huckleberry. I hope this helps someone, I can certainly provide more details if requested.

That issue has been popping up more as these cars get older.

Had the same issue on mine and here:
https://mustangforums.com/forum/gt-s...with-leak.html

High heat + no air circulation + several different materials mated together will cause problems (Plastic, metal, rubber, and coolant). The 05-09 models are 10+ years old now so, not a design flaw because hoses do wear out. Just really annoying.

All true, they are aging. The design flaw was about the placement of a heater hose in a place that is very inaccessible. Plus, I was a bit miffed at the dang car hiding it from me, ha!

I hear ya! It took me a couple of weeks to find it. With mine, I wasn't getting any puddling under car but when I parked it in the garage I was getting that musty gym sock smell and I noticed the reservoir was loosing fluid. I stumbled across one of the videos above doing a random "Mustang Coolant Leak" search on Google.

I was happy and miffed at the same time. I took the intake off to do mine. The crimped hose is the flaw i suppose. Hoses shrink over time so a crimp will deteriorate faster than a hose+constant tension clamp that can expand and contract with the temp changes.

I took a dremel tool and cut the old crimp off the old hose, just put some heater hose and some clamps. That should hold it for a while!

I had to laugh - 'musty gym sock smell"??? LOL

i have same issue, about to do repair now that weather has cooled off in Arizona
 

[QUOTE=66and06stangs;8648145]I am not good at video-ing while fixing things so this post is the best I can do. I own a 2006 GT Convertible automatic. I've only had it about 5 months, it has been a real problem child. Anyway, I found myself on the side of the road not long after buying the car, it just lost all power while going down the road, the motor just let off and I coasted to the side of the road. It was strange, it would idle fine (actually sounded good) but had no power when I put it into gear. Got it towed home... trying to figure it out I read that there are some nice sensors built into the heads that will shut down some of the cylinders if it overheats. I went, "uh, overheats?". Looked at the coolant overflow, completely empty. <<<puzzled looks>>>. Bought 2 gallons of the preferred coolant that I looked up online, thinking I'll keep a gallon around just in case. Oh, btw, I've never seen a damn drip or leak anywhere, this is what puzzled me greatly. Anyway, after putting both gallons into the car and it was still slightly low, I'm really baffled.... until one day I was toying with the car and took it for a spin around the block. I kinda horsed it, I ripped it around a corner or two, just feeling that 300hp 4.6. When I get back into the driveway, I notice a leak!!! Yes, it is coolant, but it is on the passenger side about the middle of the car... more puzzling looks - how the hell would coolant be way back there dripping?
So, to shorten the story, I did some looking and thought I found the culprit, and ultimately did. Under the intake manifold there is a coolant line that uses an elbow and a factory-crimped hose. I found a good video about this, although there wasn't much about it (hence my reasoning for this post). I spent my last Saturday taking the intake manifold and alternator off and sure enough, it looked like whomever had the car before me had squirrels or something living under the intake manifold... there were acorns, wood chips, all kinds of crap under there, along with a dripping elbow and hose. What was happening was it wasn't leaking that much at a time, and this rats nest was holding it in while sitting, but apparently dripping on the road while moving. When I ripped it around the block some of the coolant forced its way past all the crap in there, and voila, revealing the leak. Anyway, a $15 elbow, a couple of hose clamps and less than 6 inches of hose fixed the problem. Of course, i cleaned the living heck out of the top of my block down there, put new gaskets on the intake manifold, and so far, the problem is fixed. I've driven it twice and when I shine a light into the crevices I see a nice, dry hose/elbow and a dry cavity down there.
I think it is a very poor design but thought i would let anyone who owns a 4.6 and has a puzzling anti-freeze leak, this is probably your huckleberry. I hope this helps someone, I can certainly provide more details if requested.[/QUOT

[QUOTE=criminalspeed1;8711822]Let me know if you have any questions. You have to take the entire intake off, I suppose you *could* get to it if you take the front (alternator, etc) but taking the intake off made it much easier to get to the hose.