Hey guys I got an 89 cherokee laredo and the a/c works but when I push the gas to pick up speed or take off from a stop the air stops blowing out of the front vents and only blows out of the defrost vents and then when I let off the gas the air blows through the front vents again. The bottom vacuum line coming out of the firewall is disconnected because I did rid of the heater valve. I checked it and there is no vacuum when the vehicle is running on that line. But not to sure when i am driving it. Cant exactly check it when i am driving. It only does this when it is in drive. And all the other lines look to be fine. What is going on? Where do I start? Thanks

 

If your vent selector worked good before you disconnected that vacuum line, I'm sure that is what is causing your problem. Should be easy enough to hook it back up and give it a test.

 

Neither line was hooked up before and it only blew out of the defrost vents and then I hooked them up and the vents worked but it still did the same thing its doing now