Air bubble in Radiator?

[CherryCola]

I have a 2013 Mustang and I'm trying to avoid going to the shop with this one since I think I know what's wrong with it. I would just like to confirm.

My heater is only working at high RPMs. While idling to seems to go back to cold. It's almost like it only works at 1k+ RPMs.

I know cars OK and from my knowledge it sounds like an air bubble in the radiator. How do i fix this? Take the cap off with the heater on hot with the fan off? Rev up to 2500 RPMs until I see bubbles?

This is at least what I remember.

 

[pdm]

Does your temp gauge read cold or fluctuate?

 

[CherryCola]

Does your temp gauge read cold or fluctuate?

Temp is normal. 'Bout half way.

 

[PA4476]

Some cars now have a bledder valve at the higest point in the system to bleed off air. I had a 94 Mustang and the bleeder was on top of the intake, I opened it and then filled the rad with water till it started coming out the bleeder.

Another cause may be the heater core is stopped up. My 99 Silverado and a 2000 Surburban I owned both stopped up. I pulled the heater hoses off at the core and ran water through the core backwards to flush it out.

 

[BenStark]

On the new mustangs I think there is a bleed screw (like the bleed screw on the brakes). On the 05-10s it's on the cross-over tube. I would have to look at yours.

 

[Ken Ford]

Some cars now have a bledder valve at the higest point in the system to bleed off air. I had a 94 Mustang and the bleeder was on top of the intake, I opened it and then filled the rad with water till it started coming out the bleeder. Another cause may be the heater core is stopped up. My 99 Silverado and a 2000 Surburban I owned both stopped up. I pulled the heater hoses off at the core and ran water through the core backwards to flush it out.

This is probably right.You can try to back flush the core. I have mostly positive results disconnecting both hoses and running water both ways until water is clear.

 

[pdm]

What engine?

 

[CherryCola]

Some cars now have a bledder valve at the higest point in the system to bleed off air. I had a 94 Mustang and the bleeder was on top of the intake, I opened it and then filled the rad with water till it started coming out the bleeder.

Another cause may be the heater core is stopped up. My 99 Silverado and a 2000 Surburban I owned both stopped up. I pulled the heater hoses off at the core and ran water through the core backwards to flush it out.

Then just add coolant as needed? Winters are a bit more harsh up here I would hate to have a frozen engine.

 

[CherryCola]

What engine?

v6 3.7L

 

[shadowchaser59]

if it's not running hot I wouldn't think it was an air pocket. sounds to me like the thermostat is stuck not allowing the the water to stay inside the engine to heat up to run the heat. usually an air pocket will be just behind the thermostat and the air keeps the water from heating up and opening the thermostat causing it to run hot. the heater core could be about stopped up not allowing enough hot water to flow to give you heat too or the valve not opening up to all the way to allow water to flow right into the car