2006 Explorer 4.6 A/C issue

[Sethkins88]

Hey all, I've owned my 2006 Explorer for 5 years and have 185000mi. It's been a great truck. Recently, the a/c stops blowing out of the front vents when I accelerate and moves the air to the defrost. When I let off the accelerator it comes back to the front vents.

After some searching it appears I might have a vacuum leak/bad check valve. I've replaced the check valve on the passenger firewall area but it did not solve the issue. Is there another check valve that I need to replace? Any ideas on what could be going on? Thanks

 

[94Eddie]

Did you make sure the check valve was installed in the right direction? Could be a bad vacuum reservoir or a slight vacuum leak after the check valve. You can use a smoke machine to find vacuum leaks.

 

[Sethkins88]

Did you make sure the check valve was installed in the right direction? Could be a bad vacuum reservoir or a slight vacuum leak after the check valve. You can use a smoke machine to find vacuum leaks.

Thanks for the reply. I believe I installed it the same as the original. I got my check valve from the dealer. Is this the only check valve that could be causing the issue?

 

[94Eddie]

I don't know of another check valve that could cause this issue. There could be another minor vacuum leak somewhere that can cause it. You can remove the check valve and blow into it to make sure it works and you have it in the right way. The side you blow into that will allow air to pass should go toward the point it enters the firewall on the passenger side.