Coolant smell

MustangS197_1995

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I'm getting a very slight coolant smell when my heater is on. Not necessarily worried. But I my first thought was the heater matrix is on its way out. No coolant in the passenger footwear or anything and you can smell it in the engine bay.

I'm hearing the pipes in the engine bay may be leaking slightly on the connectors on to the exhaust manifold then coming up through the CAF.

Are these the said pipes for the matrix? If so does anyone know the part numbers for them please? Would rather try swapping the pipes then pulling my dash out to find its fine haha

20260604_141511.jpg
 

Kev555

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V6? Yes that's the heater supply pipes, not sure if the same issues arise looking at your pipe layout but the heater supply pipe leaks under the inlet manifold on the 4.6. Somebody will be along later that's more familiar with your engine and the places it leaks.
 
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TexasBlownV8

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Add a little coolant leak dye, run it, use a UV light at night to easily find the leak. If there is a serious leak, the coolant level will drop, so keep an eye on that.
The alum t-stat housing shouldn't be leaking, but if you reused all the hoses and spring-clamps, it's possible there is a seep from one of the hoses; UV light would show it.
On a family member's 4.0, one of the heater hose lines is starting to seep a little at the 90* into the firewall connection, but no smell from inside.
Smell can be coming in from the engine bay, hopefully! Changing out a heater core is NOT easy; did one once.
 

GlassTop09

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Add a little coolant leak dye, run it, use a UV light at night to easily find the leak. If there is a serious leak, the coolant level will drop, so keep an eye on that.
The alum t-stat housing shouldn't be leaking, but if you reused all the hoses and spring-clamps, it's possible there is a seep from one of the hoses; UV light would show it.
On a family member's 4.0, one of the heater hose lines is starting to seep a little at the 90* into the firewall connection, but no smell from inside.
Smell can be coming in from the engine bay, hopefully! Changing out a heater core is NOT easy; did one once.
+1.........this.
 

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