Weird A/C Issue
Weird A/C Issue I am finishing up some final things on my TA build and came across an odd issue. My A/C and heat work and the blower works but it won't switch to blow out of the dash vents. Only 3 positions work: off, windshield defrost, and the vents by my feet. If I switch it to blow out of the dash vents I get nothing. Anyone have any ideas?
Reach back behind the intake and check the small black (hard plastic) vacuum line that connects to the intake port. At the end of that line that connects to the port, there should be a little rubber cover on that end. It might be stuck onto the port still. If it falls off, your vents will be stuck in the last position. They are vacuum actuated.
When reaching back there be careful about that little rubber end cover, it could be hanging on to the end of the line barely....
If it happens to still be on the port...pull it off, put it back on the end of the line, then push it back onto the port. If you lose that end you need to go to the auto parts store and get a new one.....just have to go through all their little rubber tube ends till you find the right one that will fit.
This vacuum line comes out of the PCM wiring bundle and runs to the back of the intake on the passengers side, it connects right next to the MAP sensor. From memory....the port is just under the MAP sensor...not positive. The port on the back of the intake points directly towards the passengers side. So you would reach back with your hand and feel for that port...then push the rubber end and line onto it....
Heres a picture I found: See the little port right under the MAP sensor....
https://www.google.ae/search?q=ls1+m...neTdHbEc2zM%3A
Here's what the rubber line end piece looks like...EXCEPT yours will be a straight piece...not a 90* turn down piece. Then the hard plastic vacuum line connects into that rubber piece.
https://www.google.ae/search?q=ls1+m...fbQ2bonAz7M%3A
.
When reaching back there be careful about that little rubber end cover, it could be hanging on to the end of the line barely....
If it happens to still be on the port...pull it off, put it back on the end of the line, then push it back onto the port. If you lose that end you need to go to the auto parts store and get a new one.....just have to go through all their little rubber tube ends till you find the right one that will fit.
This vacuum line comes out of the PCM wiring bundle and runs to the back of the intake on the passengers side, it connects right next to the MAP sensor. From memory....the port is just under the MAP sensor...not positive. The port on the back of the intake points directly towards the passengers side. So you would reach back with your hand and feel for that port...then push the rubber end and line onto it....
Heres a picture I found: See the little port right under the MAP sensor....
https://www.google.ae/search?q=ls1+m...neTdHbEc2zM%3A
Here's what the rubber line end piece looks like...EXCEPT yours will be a straight piece...not a 90* turn down piece. Then the hard plastic vacuum line connects into that rubber piece.
https://www.google.ae/search?q=ls1+m...fbQ2bonAz7M%3A
.
Last edited by LS6427; Feb 19, 2016 at 07:49 AM.
Your the man! Thanks, I would not have figured that out. I am 99% sure that's the problem b/c I switched to a 92/92 set up and I capped that port on the intake up and zip tied the vacuum line up out of the way. Had no damn clue that went to the HVAC. Can't remember what I assumed it was but I was clearly wrong.
