Auto Air Conditioning & Heater Repair: follow up, dodge ram 1500, c switches

Question
QUESTION: i have a 1998 dodge ram 1500 p-u. 5.3 ltr. engine. here's my problem. i live in southern arizona. hot and dry climate. when i first turn on the a/c all is fine. when i start to accelerate the a/c switches from the dash vents to to defroster vents. i was told to change the acutater so i did. perhaps therez' more than one?  AIR blows cold, but does us no good coming out the defroster. thanks for your  attention. steve

ANSWER: Hi Steve

You may have a system with vacuums.  I need to know if you have an automatic ac system or manual.  If your control has an auto button and is digital you have an automatic ac control.  If not then you have manual ac and it is controlled by vacuum.  You will have a check valve that controls the door from moving while you accelerate.  Let me know if when you stop accelerating does the ac move back to the panel.

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QUESTION: yes it does... since your in florida, and im in az. could u tell me what im lookin for. thanks i apreciate your time and advise. i think this service is awesome. best regards steve romero.

Answer
Look in the engine compartment on the passenger side.  Near the firewall you will find the accumulator (black or aluminum bottle).  Look in the that area you will find a vacuum hose usually black in color coming out of the firewall follow the hose to the engine and you will find the check valve.  Let me know if you need anything else or if I'm not clear in my answer.