I have a 1993 Volvo 940 (NON Turbo) it has 288000 miles on it. I bought it for a good price needed a head gasket... replaced head gasket, head bolts water pump, radiator, hoses and belts...so I found this piece laying in the back of the engine bay, can't figure what it is looks like it might be broken...it was connected to a small cable...I have looked everywhere for what it is to put it back where it belongs....HELP does anyone know what the heck it is?...and what it does...I feel kind of silly but it is really throwing me off

 

Heater control valve.

 

Thanks I will order a new one in AM, while it was not hooked up it did still have a small cable attached to it hopefully it seems to be a simple fix...not like the old 544's or 122's

 

I went out and took a look at the area and the "cable" and now see that the cable is actually a vacuum hose and what they did is just bypass the whole setup with a simple pass through water line...I am wondering what specific function this valve has?

 

It's a mystery. There's just no way to figure out what something called a "heater control valve" might do.

 

Looks like it may be missing a hose barb.

Your car has a vacuum controlled cabin heating system. It's possible someone removed the old heater control valve from the coolant line because something else in the system was broken and they were too lazy to properly troubleshoot or fix it.

If you have heating system problems after installing the new heater control valve, start following the vacuum line and look for broken or cracked lines, tees, etc.

This may help you: Volvo 760GLE 1988 Heater intermittently goes to defrost

 

 

I am in AZ, in the desert, most days are cool when it's only 98...no need for heater however I will replace the part and do it right thanks for all the input...part is quite cheap on eBay as low as 19.00 so what the heck

 

if you dont need a heater at all, you could always just disconnect the heater core entirely, and loop the engine size heater hose outlets together with a spare piece of the right size hose. blow any old coolant out of the heater core, and voila, no heater.

but... don't winters get pretty cold there when you visit places at higher elevation at night? I remember the Kaibab Plateau being snow covered in May one year quite awhile ago.


the cable control heater valves were used on 240s before around 1991 or 1992. the heater lever on the dashboard directly push/pulled the cable to open/close the heater valve.

 

FYI,the new redesigned ones are plastic.

 

what vacuum hose connects to this valve? the White PVC?

 

if you are asking about the vacuum hose connected to the heater valve, its one that comes through the firewall from the heater control panel on the dashboard center console.

 

Funny thing about automobiles ... they're mobile. People use them to drive to other places. You never know when someone will want to go visit Duluth.

 

I may be late to this discussion, but I went through this on my '91 740 last year, and ended up replacing that heater valve with an all metal replacement that was found on older GM cars. I was iffy on replacing it with another plastic piece, so I nabbed this:


It has worked perfectly, and I feel a bit better knowing it's all metal after reading a few threads where plastic replacements didn't last nearly as long as the original plastic.