Hey guys, I hope someone will be able to help me out on this one and that it is a relatively easy fix. The title explains the problem pretty accurately, my 1986 760T will only blow air out of the vents when under throttle. Basically when I am going under 60 the amount of air that comes out can barely be felt. I replaced the blower motor about a year ago and have had no problems with it. I can hear it spin up and stop when I turn the car on/off. I have a good deal of the paneling taken off, but I wouldn't think that that is causing the problem.

The car had a number of problems when I got it, and when it was finally fixed (ie running) I was so thankful I was willing to overlook small things like the fan not blowing, and the radio not working ( antenna goes up and down and worked before I got it fixed so it is probably a ground somewhere but I cannot find it). So anyway, I am driving a little bit more now and am not looking forward to another Texas summer with no air/ radio. Save me.

Again, any help would be awesome and thank you in advance.
-Cole

 

Since it's a 760, you have Automatic Cimate Control right? Can you hear the fan motor running on high when you roll the temp dial to its coldest position? In other words, I'm trying to understand if the blower is working and the air doesn't make it out the vents or whether the blower motor itself isn't even blowing. The ACC is a pita. I just recently sold my 84 760T w/ ACC. The a/c sensors were messed up and it would not blow on high if the temp was set more than 10 degrees different than actual interior temp. To get the a/c to blow on high in the summer, I had to set it to 80. When I heard the blower slow down, I'd ease it to 75, then 70...

 

Thanks for the reply! You were right, I have ACC and I guess it could be an issue with the ACC but haven't really looked into what sensor or relay would have to be replaced. I am really thinking that it is an intake issue, I've heard of plastic bags or paper getting in the way of the intake. I have checked the vent, the one by the front passengers feet and didn't feel/see any bags in the way of it, and if it was truly clogged i don't think it would blow at all. The fan definitely turns/runs and blows when the car is started it is just very weak. I have no issues with the temperature settings. When it is set to 80 or more it blows hot, not quite as hot as on my old 240dl, but it works. And when it is set lower, it adjusts just fine, a/c needs charging. Also, the control panel seems to work just fine since it switches from defroster, to fan, etc. rather easily.

Literally, on the freeway everything works wonderfully, but when I exit and come to the first red light, stop sign, or even just slow down to 30-45 mph speed limit, the fan blows a tenth the air it was blowing under throttle/ at 65-70mph.

Could it be a grounding issue? I don't think the bolt that the grounding wire on the fan got screwed in all the way because there were threading issues on that one hole. I figured that when I heard it turn on it was good to go, even though the ground wasn't 100% pinched down.

 

Ok...when this happens, do you have it set to "auto"? Because the ACC will raise and lower the fan speed at will once the proper temp has been reached. And yes, grounding is always an issue with Volvos. Does it still do it when you move it to max, or what ever it is to the left of auto? Because that position is a fan over ride...it should blow high regardless of temp...ideally.