Apologies if this has already been posted, but I looked through tons of forums and couldn't find anything exactly like what I'm going through. As the title says, my vent selector works for everything (defrost, floor, front, etc.) except for the MAX A/C setting (the one that recirculates air). If I use the MAX A/C setting, the air blows through a mixture of defrost and dash/face vents.
I just purchased this Jeep a couple months ago (2000 Jeep TJ Sport w/ 4.0L I6 and 32RH), and it had a ton of issues including a vacuum leak that was messing with the vent selection. I was actually going to go with a different rig due to the work that was needed, but I just couldn't pass up a 2000 model with only 73k miles. Anyway, I fixed that vacuum leak (at least the one leak that I found), which fixed almost all the vent selection issues as well as the cruise control since that also runs on vacuum (a nice two-birds-with-one-stone situation). After flushing the heater core / evaporator and charging the freon, the entire HVAC system is fully functional with the exception of the vent selection for the MAX A/C setting.
I've visually inspected the vacuum lines under the hood as well as any I can see under the dash just by removing the glove box door and a couple dash panels. I have not yet ordered a vacuum tester kit to actually measure anything scientifically. I'm hesitant to lean towards another vacuum leak because the "regular" A/C setting and the fresh air vent setting both work instantly. From what I understand, these all use the red vacuum line just the same, but there is a very high chance that I'm not fully understanding the situation.
One strange thing I've noticed is that if I use the "regular" A/C setting to get everything blowing through the dash/face vents, I can then switch the setting to MAX A/C and everything keeps blowing through the dash/face vents. What would you guys recommend my next step be? Vacuum tester kit to check for vacuum? Replace HVAC control panel? Something else?
Thanks so much for any help, and again apologies if this is a repost. I've seen plenty of posts about the front vents not working, but I've never seen a post where they're only nonfunctional for the MAX A/C setting.
I just purchased this Jeep a couple months ago (2000 Jeep TJ Sport w/ 4.0L I6 and 32RH), and it had a ton of issues including a vacuum leak that was messing with the vent selection. I was actually going to go with a different rig due to the work that was needed, but I just couldn't pass up a 2000 model with only 73k miles. Anyway, I fixed that vacuum leak (at least the one leak that I found), which fixed almost all the vent selection issues as well as the cruise control since that also runs on vacuum (a nice two-birds-with-one-stone situation). After flushing the heater core / evaporator and charging the freon, the entire HVAC system is fully functional with the exception of the vent selection for the MAX A/C setting.
I've visually inspected the vacuum lines under the hood as well as any I can see under the dash just by removing the glove box door and a couple dash panels. I have not yet ordered a vacuum tester kit to actually measure anything scientifically. I'm hesitant to lean towards another vacuum leak because the "regular" A/C setting and the fresh air vent setting both work instantly. From what I understand, these all use the red vacuum line just the same, but there is a very high chance that I'm not fully understanding the situation.
One strange thing I've noticed is that if I use the "regular" A/C setting to get everything blowing through the dash/face vents, I can then switch the setting to MAX A/C and everything keeps blowing through the dash/face vents. What would you guys recommend my next step be? Vacuum tester kit to check for vacuum? Replace HVAC control panel? Something else?
Thanks so much for any help, and again apologies if this is a repost. I've seen plenty of posts about the front vents not working, but I've never seen a post where they're only nonfunctional for the MAX A/C setting.
