Joe Madden

I like my AC just like i like my women. Blowing hard! Well, had ac issues since i bought the car. Did my normal checks for voltage and all is well. Did the ac check? Freon is all good. Ac blows cold, just not hard. I replaced my blower fan 2 times and every vacuum line i could get my hands on. Replaced all check valves, still blows cold but not hard. Air comes more from the defrost vent than the middle ac vent. I pulled apart 2 vettes over the last week and followed all the lines around all accuators and dampers. Still nothing, so i swap that little plastic connector out that is on top of the fan box on the passenger side and BOOM! Full on ac. Blows like a new car again. I read 1000 posts about ac troubles and i have never seen anyone say anything about that harness. Hopefully this helps at least 1 person.

Joe Madden

it is a 90, but all years from 84 to 96 have it. It's under the hood, passengers side, the only harness on the top of the air box assy. There is 2 connectors side by side. When you unplug the 2 connectors (connectors have multiple wires, like 6/8 in each harness) idk what the part is called but it has 3 screws holding it in the plastic air box. When you unscrew it and pull it out, it has an aluminum heat sink on it and a sensor. I pulled it out and put a different one in there, now the state called FEMA because the air blows like a hurricane! I have been pulling wires, sensors, vac lines, all kinds of ish and that Lil bastard was the issue the whole time.

Joe Madden

I didn't know that, I'm actually out in my 90 IN HOUSTON! I haven't driven this car in the summer since I got it. Ac blowing beautiful! #

warrior4jesus

How about a picture or 2 so we can see what you are talking about.

xrav22

Yes a pic please, I was mulling around armor all ing found my top evaporator line seal was broken. I put some silicone adheasive and glued it back, that seems like a area for a leak. Can anyone confirm I think my air is blowing harder now.

ctmccloskey

It sounds to me like your C68 is trying to tell the Blender Box to do something and it is not responding. The blender box is primarily there to mix hot and cold air together to make the temperature you select. The blender box has several vacuum lines going in and out of it and I believe it controls which vents are active. I may be wrong, you need an expert to give you his thought.

Contact Bryan Thompson at BATEE.com as he is THE expert at C68 systems and he has a business where he repairs these things all the time. Bryan is an incredible resource for Digital Dashboards and C-68's on our C4 Corvettes. Bryan has helped me resolve dash and C68 issues over the years.

This link will take you to the right section of his web page where he describes the problems with the original design and how to fix them.

http://batee.com/corvette/dcrg/services/c68repair.html

Good Luck with your vent problem! Look at the bright side, at least you have air blowing out of the system!