Air Conditioning problem
1993 Plymouth Voyager 6 cyl Front Wheel Drive Automatic 216000 miles
My 1993 Grand Voyager has an issue of slipping the damper from panel circulation to floor circulation whenever I give the vehicle gas, such as on any highway incline. As soon as I let off the pedal and turn off the AC then restart it goes back to the panel just fine. It sounds/feels like some sort of vacuum issue. I have even had the in dash control unit replaced without any luck. I have not had any luck locating the vacuum line/s that would possibly effect this.
Simple fix. In the middle of the firewall under the windshield, under the hood, is a small check valve in the hard plastic vacuum hose. It's the size of a stack of two nickels. Replace it with one that's about two inches long and 1 1/2" in diameter. It has a small storage chamber to prevent the loss of vacuum during acceleraion or when going up long hills.
The system is spring-loaded to default to the defrost position for safety reasons. If the system isn't working properly, your feet might freeze but you'll be able to see.
The dealer's parts department has the new check valve, but you can also find them in the salvage yards.
April, 5, 2010 AT 4:32 AM
After much research I have found the correct part is a very hard to find vacuum valve canister part number 4677204. It is located off the brake vacuum assist located very near the master cylinder. It is connected to the very small (one of two) vacuum lines located there. My 1993 Grand Voyager already had this larger part (the original part was a much smaller canister). The canister is slightly larger than the size of a black 35 mm film canister. The part is supposed to be sold in the HELP section of most parts stores but I have checked several with no luck. It's very easy to find the smaller version in that section but it comes with an extra feed opening and is too small to hold much vacuum reserve. Additional info can be found by googling " Plymouth 4677204"
April, 9, 2010 AT 11:46 AM
Awesome news, we're really glad you were able to find that info and get your vehicle back in to action. Thank you for using 2CarPros. Com. We appreciate your donation and look forward to helping you in the future.