Coolant smell 2005 Mustang gt - Ford Mustang Forum

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post #1 of 10 (permalink) Old 05-03-2010 Thread Starter
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Coolant smell 2005 Mustang gt

i have a 2005 gt and have recently started smelling coolant. It isnt a strong smell but is noticable. The smell is even around when the car isnt running. I have not found any leaks.... nothing on the ground, no white smoke out of the exhaust... temperature of the motor has not gone up. No issues with how it runs at all.

The car does not overheat and i had it hooked up to a scanner and on sct datalogging and could not find anything wrong.
The coolant looks old and should probably be changed but i was wondering if there is any known issues or recalls or problems with the lines or coolant resevoirs?

i know it isnt headgaskets because it does not smoke, has no coolant in the oil and does not overheat.

any help would be great

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post #2 of 10 (permalink) Old 05-04-2010
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how many miles?

prolly about time to have it changed. i used motorcraft yellow. after installing my supercharger

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post #3 of 10 (permalink) Old 05-04-2010
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Coolant Leak ?

Only way to tell for sure is to get the proper adapter and pressure test the cooling system...with a manual cooling system see if there are any external leaks. Such a tester may be available to be borrowed from a parts store. With such a test any leaks become obvious as they drip on the ground under car...or worst case scenario...a leak inside car from heater core.

I am not familiar with most likely leak areas on this car. I would lst look for an overfilled plastic tank spewing from the cap, any hose leaking near that tank, near radiator, around water pump, or a leaking hose at rear of engine block going to heater core at firewall.

There is also a TSB related to heater core leaking on page four of the TSB list. TSB 6-21-19.

If no external leaks are found after doing a careful inspection of the system under a pressure test, then leak would be internal...a cylinder head gasket issue. There is a test also to test at cooling system for exhaust gases in coolant. Other tests at spark plug holes can test for water in any cylinder.
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post #4 of 10 (permalink) Old 05-04-2010 Thread Starter
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thank you for the advice.

i do not smell it inside the car... the floor is not wet. The only time i can smell it is when im walking around the front of the car or can very faintly smell it when the windows are down. I do not smell it inside the car. When i put my nose in the engine bay i can smell it stronger around the thermostat and coolant resevoir but i do not hear any leaks or see anything dripping.
It seems to be a very very faint leak.
more frustrating than anything....

the car does seem to have older coolant in it. but that wouldnt cause it to smell more than normal would it?

I hope it is not a heater core because i hear it is an expensive job to replace

Last edited by adams; 05-04-2010 at 06:55 AM. Reason: spelling
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post #5 of 10 (permalink) Old 05-04-2010
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Maybe you just need a new cap for the coolant overflow tank. Maybe it's just venting too easily and not holding the pressure. That would be the first thing I would change if you don't see any leaks.

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post #6 of 10 (permalink) Old 05-04-2010
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I have the same issue, I took it to the dealer they pressure tested it and it held 17 lbs for 45 minutes, no leaks. The only thing I was told is it could be a bad resevoir tank. STL says that has been an issue in the past, improper fit of the coolant cap, so I bought one and will change it and the coolant soon

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post #7 of 10 (permalink) Old 05-04-2010
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cap or tank

Sorry I forgot to mention to check the cap.

This type of system is new to me...a former tech. I looked at my car and noticed that there is no coolant overflow tank as previous cars of all makes have had in recent years.

I also noticed that now, when car is cold, I can squeeze the upper radiator hose and hear air going in and out of the radiator cap. That means the system is open to atmospheric pressure when coolant is at outside air temperature.

A failing cap or plastic tank which does not properly seal (threads) the cap could be an issue as others here have suggested. Old coolant should make no difference in whether a system leaks or not.

Ford suggests replacing coolant every five years. Time for me to do it also. I need to do mine but don't trust the dealer to get all the old coolant out of the system, so will do it myself, flushing with water completely (while thermostat is out of the car) and draining before replacing with new coolant.

Others in this forum, in the past, have recommended which coolant to use. I cannot recall what they recommended. You'll notice in pics of new Mustangs, that Ford now uses a Red coolant instead of the Yellow used by the Factory in our cars.
I do not know the difference. Maybe Prestone Green is o.k. also.
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post #8 of 10 (permalink) Old 05-04-2010
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Check the filler neck or possibly a bad cap.

1965 Mustang Coupe
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post #9 of 10 (permalink) Old 05-04-2010
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Answer to a question you did not ask---what coolant to use

Read entire article and DON'T RELY ON COLOR ONLY to pick a coolant.

Ford uses a HOAT (Hybrid Organic Acid Technology) coolant for The Mustang. It is an extended life coolant. Their name: Motorcraft Premium Gold Engine Coolant. VC-7-A meeting Ford spec WSS-M97B51-A1.

The plastic bottle is called a Degas that term to find it.

Note relating to above article: The mustang does not have a heater valve, therefore coolant runs constantly through the heater core summer and winter.
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Coolant Color

All coolant is clear when made. Manufacturers add color to coolant to identify it. Some aftermarket manufacturers may add a specific color to fool us into paying a higher price for something we're not getting.

Mixing different types of coolant will most likely NOT harm an engine, but it WILL shorten the life expectancy of that coolant as a whole.
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