Ok guys,
I'm really confused. I'm trying to fix my heat in my 94 Z28.

My brother said the same thing happened to him and that it was the heater control valve. He pointed to a tube crimped in to the heater core hose that runs from the bottom of the water pump, next to the fan.
when I went to order one at Autozone They gave me what I normally thought of as a control valve. A vacuum diaphram with 3 holes for hoses.
however this is nowhere to be found on my car. I taking a wild guess that this wasn't actually used on my car and somehow the thermastat handles this. (merely a guess) but when I double checked the part number it was right. and the heater core hoses they sell do not have this tube.
Can someone explain.

 

AFAIK F-bodies dont have such a valve anywhere. Flushed out your heater core recently?

 

Good, I thought I was stupid for a second.

So what is that tube? Once again it crimped in to the middle of a hose which runs from the water pump to the heater core and has an arrow pointing towards the heater core.

 

Just the way it is on these cars. One goes to the core, one comes from the core, and they both turn into metal tubes and back to rubber at one point. I'm sure someone has an explanation for it but I sure dont. Just flush out the core.

 

well, I'll try the flush

 

Actually, that metal piece crimped onto the heater core inlet hose near the water pump is in fact a flow control valve. However is it not a heater control valve. Like someone said earlier, to my knowledge these cars do not have a heater control valve, unless they are talking about a vacuum valve of some sort to open and close the heater door. The flow control valve can only be replaced with the whole heater hose assembly, which is both the inlet and outlet heater hoses. It's not cheap either, I think it was like $68 from Jason Cromer. I know this because I just looked into changing my heater hoses and I will do so this weekend.

I had the same problem too--bad heat. More than likely it is a clogged heater core. What I did with mine was flushed the whole coolant system with Zerex Coolant Flush, then flushed it with water. After that I took the heater hoses off, both inlet and outlet, and backflushed the heater core, meaning I shot water in through the outlet and let it drain through the inlet. By the way, the outlet hose is the top hose, the one with the system bleeder valve on it. I ran water through it until it was clear. I had some chunks of stuff some out of it when I did that, so more than likely that was the problem. After that I flushed it from the inlet through the outlet and repeated the process about 4 times. Put everything back together and filled the system.

Unfortunately I wasn't able to test it out because it turns out I damaged the outlet heater hose when I was taking it off, so I have to change out the whole heater hose assembly. Luckily I had already bought a hose assembly because I knew the inlet hose (ironically the hose that wasn't damaged) was leaking very very slowly. Unluckily, I didn't have my Torx socket set at home, it was 2 hours away at college. Plus it was Sunday night and no stores were open. The heater hose assembly is bolted using a T-40 Torx socket. So for anyone who is going to do this job, you need a Torx socket to change the heater hose assembly!

Hope that helps.

 

There is a service bulletin for certain years of camaros that entails the heater core box I beleive. I read about it when I used to be a mechanic. If I remember correctly, it was about a bad seal around the heater core box. Which in turn dissapated the heat that should have been coming through the vents. Mine never really had good heat anyway. Just the nature of the beast I guess.

 

Flush your heater core. I guarantee it's clogged. These cars are notorious for that. Take the two hoses off that come from each side of the core. Take a garden hose and flush water through one side until you get clear water coming out the other. Then do the same to the other hose. Put the hoses back on and tada.....you'll have heat. You'll be amazed of all the black and brown crap that comes outta there. I had the same problem and having never had issues with the heat in this car before I thought my core was gone. As recommended to me I did the flush, and a bunch of black sludge and crap came out. After that I have had nothing but great heat ever since. Actually had my heater core go out on me a few months back so I know that's not your problem. Cause you'd have a passenger floor full of coolant like I did . Another thought if the flush doesn't work. A guy just a week ago or so on this site had a similar problem and before being recommended the flush he did some investigating. He checked all hoses and found out one to be crimped off and basically cutting off all flow through it. After replacing the hose he was back to normal. Try the flush first, but if it doesn't work, check into that.

 

I was able to replace my heater hoses this weekend. It was a tough job for me. I ended up taking the alternator off to get more room. If you were bold enough to take off the power steering pump and mounting bracket you would have a much easier time. I didn't want to take the power steering pump off because I didn't want to have to bleed the system. It took a lot longer to get the heater hoses out then to put the new ones in, but I got them in. No leaks! And I actually have heat now. So I would definately try flushing the heater core first before replacing it or doing anything else to the car to try and get better heat. I would guess that it is the problem ~90% the time.

 

I flushed my core... then the rest of the system.

my heating problem went from cold to luke warm... if that... still bad heat.

Anybody else got any info on that TSB that Reds929 posted?

 

I'll try to find it again. It was on that new system, where all the service manuals for every car foriegn and domestic (from 1980? I beleive) are on 5 DVD's. Its a pimp setup. Too expensive though.

 

I just got finished doing the flush as outlined in this thread;

http://web.camaross.com/forums/showt...hreadid=191218

When I first flushed it nothing really came out....it ran clear pretty quick. So I switched it around a bit and stuck everything back together and MAN, did it ever get hot! My heater used to suck so bad, no one liked riding in my car in the winter. Even when the temp got close to red, the heater still blew only luke warm (if that). If you turned it up past the second notch, forget about it, just like having the a/c on. But since I live in Texas, the winter months are usually kinder to me and shorter so I just toughed it out for the two or three months with warm sweaters or a jacket. Now I have a baby girl due in a few days and I didn't want her to come home as an ice cube so I flushed the core and it works like a charm! Try it again like the pictures in the link show and maybe you'll get better results. Good luck!

 

well, It's getting colder, and my car ain't any warmer.
any ideas?

 

I just fixed this problem last night. Mainly due to a clogged heater core. How did you flush yours? You probably will need to do it again, remove the inlet and outlet hoses off the waterpump. Clear the outlet hose from the opti, i had mine spraying down to a bucket. Use something that will bottleneck the stream coming from the garden hose (i.e. a spray nozzle) This is what I did and the pressure was enough to remove chunks of what looked to be clay from my heater core. After you're done with that replace the hoses, fill the radiator, with the car off, open the bleeder valve on the top of the thermostat housing. Fill the radiator till a steady stream is flowing out of that bleeder valve, close the valve. Put the cap back on the radiator, start the car. Wait till your car warms to thermostat temprature. This is building pressure in your coolant system. Open the bleeder valve to the heater hose now. Located on the metal 4" peice of line on the inlet hose you previously removed. Aim it away from your alternator, wait till a steady stream is flowing and close valve. Wait for coolant pressure to go down (motor cool down) open radiator cap, top off fluid. Done

When you say you're temprature coming from the vents went from cool to luke warm, I'd almost have to say you just need to flush that heater core better. It took me all of 15 minutes to finally start getting chunks of that corrosion out of there. Now I have HOT heat.

 

No joke, I flushed it for a half hour, after the water was clear. Then I went and flushed the entire system. I can't imagine that still being the problem.

Heres a really weird one for you though. after driving for about 20 minutes, if the fan is on low, a do start to feel the heat. enough to actually sorta keep me warm. along with it is an odd smell. Don't ask me why but it resembles the smell of steam from a clothing steamer. I'm wondering if it's the seals on it. I check it eventually