a/c airflow changes when accelerating

[sispy]

Just bought a 2003 Expy EB 4x4, and realized that when accelerates the airflow from the a/c changes, like when switched to feet or defrost. As soon as I ease on the pedal the airflow returns to normal. The first thing that crosses my mind is something about a vacuum line or something. Any advice would be greatly appreciated.

Frankie.

 

[green03]

You are on the right track.... I would suspect a vacuum hose bleeding off vacuum. When you accelerate you lose your vacuum and it is bleeding off and not storing it because you have a leak.

Matt

 

[JUST4FUN]

Have you had the battery out for any reason?
their is a vacuume ball or canister under the batt if it (the
batt)got "dopped" back in this might of cracked it

 

[sispy]

Sorry for the delay but I've been very busy and didn't have time to post an update. Thank you guys for your comments. Yes, both of you were right, the problem was that apparently during some service before I got the Expy some "mechanic" forgot to reinstall the pipe that connects to the EGR valve, in fact it was resting peacefully over the engine. And there was a disconnected vacuum line between the batt and the firewall. Now the AC works like a charm. Thanks again for the help.