Air Conditioner Acting Up When Accelerating

[drewkeen]

The is on a 1999 Explorer 5.0L. The A/C has been acting up when acceleration or driving up a large hill. I assume it is a vacuum issue as it only happens when there is low vacuum in the intake manifold. It blows great when cruising on flat ground, downhill or at idle but when you accelerate or go up a large hill it stops blowing from the vents and switches over to the defrost vents.


Where are the hoses that control this located and where should I start to search?

 

[shamaal]

The most poular thread with pictures and stuff is at:
http://www.explorerforum.com/forums/showthread.php?t=169945&highlight=vacuum+globe

You are correct in your determination that it is a vacuum problem. The reservoir has a check valve that closes under acceleration to prevent the engine pressure change from affecting the environmental controls, in this case the cabin recirc vent. A common problem with the globes is that they fill with condensation and just need to be drained.

Good Luck!

 

[Troubletwin]

The is on a 1999 Explorer 5.0L. The A/C has been acting up when acceleration or driving up a large hill. I assume it is a vacuum issue as it only happens when there is low vacuum in the intake manifold. It blows great when cruising on flat ground, downhill or at idle but when you accelerate or go up a large hill it stops blowing from the vents and switches over to the defrost vents.


Where are the hoses that control this located and where should I start to search?

I am having a similar problem with my 2002 explorer xls. Under acceleration it turns from vents to defrost. It does not return to the vents once you back off of the accelerator. Trying to figure out which vacuum line controls that so I can replace the line or check valve. I need help.

 

[Pete Deering]

I am having a similar problem with my 2002 explorer xls. Under acceleration it turns from vents to defrost. It does not return to the vents once you back off of the accelerator. Trying to figure out which vacuum line controls that so I can replace the line or check valve. I need help.

You did not state if you have a automatic temperature control model?
What engine do you have?