Since I bought my XJ in Feb of 09, a portion of the air comes out the defroster no matter what setting it's on. I went over the hard lines from the intake to the vac ball with no luck. Last night while researching an AC issue, I came across a reference to a check valve on the intake manifold. After testing mine, I could blow through both ends. I then spent last night and this morning looking for a replacement for the check valve on the rear of the intake manifold that connects to the HVAC, Cruise, and vac ball. Now I have some part numbers to share.
The original part number was 4306923, and that has been superseded by 4549209. The new valve is a bit bigger than the original and has a small built in vacuum reservoir. The best part is that I was quoted a price cheaper than a universal would be from a parts house.
This seems to be a common problem with mid 90's Ram's. Those guys are complaining that the nipples don't fit the factory hose sizes and you have to do some adapters. I'm going to assume you would with a Jeep also. I'm probably going to swing by the dealership down the street from my house this afternoon and order one. I'll report back once I have it.
The first picture below is the new setup, the second is the original valve.
The original part number was 4306923, and that has been superseded by 4549209. The new valve is a bit bigger than the original and has a small built in vacuum reservoir. The best part is that I was quoted a price cheaper than a universal would be from a parts house.
This seems to be a common problem with mid 90's Ram's. Those guys are complaining that the nipples don't fit the factory hose sizes and you have to do some adapters. I'm going to assume you would with a Jeep also. I'm probably going to swing by the dealership down the street from my house this afternoon and order one. I'll report back once I have it.
The first picture below is the new setup, the second is the original valve.
