heat problem...heater core or blend door??

I have taken my 2001 s-10 to two different shops and got 2 different estimates. One says that my blend door motor may be bad. The other one says that my radiator and heater core are clogged and need to be replaced. Either way I have no heat. How do I know who to trust or believe. My blower works fine, every setting. I have reverse flushed my system and run the prestone flush to no avail. I haven't used the "diy" carwash trick yet but I'm very tempted. I also don't know where the drain plug on the radiator is. Haynes says its on the lower left side of the radiator but I'm not sure what left they are referring to. Help please.

First, the drain plug is on the driver's side of the radiator. My '95 even has a hose coming out the bottom of the truck, just below this plug, for the antifreeze to drain from. My plug need only be turned 45 deg to drain fluid but I don't know how yours is set up. As for the heater core being clogged, with the truck at operating temp turn the heat on hot and the fan on high. Feel the hoses going to and coming from the heater core, your haynes book should tell you which they are. If they are hot your heater core is fine, if not it is probably blocked up. Good luck.

ok, well left is the drivers side. reach all the way down.. along the side of the radiator. now hopefully you can feel a knob. turn it towards the washer resorivor (turn left).

i had a bit of trouble finding it until i crawled under the truck the find the hose.

If the drain doesn't have a hose on you can usually slip one on there, which I highly recomend. Leave it on if you can

If the drain doesn't have a hose on you can usually slip one on there, which I highly recomend. Leave it on if you can


Here the problem I have now. I removed the housing that holds the air filter to better access the left side of the radiator and only see a pipe and hose that are connected on that side. I looked in the haynes manual and it shows a wingnut type of plug which I can not find to save my life. I have full access to that side of the radiator. Am I looking in the wrong place? And if I do find the plug does it come out or do I just turn it to release the fluid from a different hole?

your looking in the right place.... you need to feel around a little bit, you can probably find it with your index and middle finger. just turn the wingnut a bit so fluid can come out. the wing nut probablt has a hole that, when lined up will allow the antifreeze to flow through to and then the tube.

Thanks guys. I ended up pulling the lower radiator hose. I was going crazy and couldn't find it and refused to waste another second on it. Thanks for everything.

Did this solve your problem with the no heat issue?Just a heads up but your heater core may have been air locked.

No still have no heat. And guess what! This morning on my drive in to work I got a hint of an antifreeze smell in the cabin. Then POOF. Steam everywhere. Coming out of every vent. The passenger floor isn't wet but I'm thinking maybe the heater core just went. I had to pull over because it was so thick that I couldn't see. Any ideas?

probably the core, which was probably the reason why you had no heat.

you'll have to investigate first, it might be a burst hose. Just don't start it until you have atleast a temp repair done.

Rarely is the heater core clogged. Disconnect the heater hoses and flush it out (heater core)with a water hose.

heater core blew out..

Rarely is the heater core clogged. Disconnect the heater hoses and flush it out (heater core)with a water hose.

now that u have mentioned this tidbit, i was just wondering what u thought was happening with mine. i have a 94 2.2 and when i start mine up and drive it for a little, my oil pressure is kinda high, then i get a strong whiff of antifreeze and the oil pressure drops, but i still smell strong antifreeze scent. nothing leakin underneath or in the cabin. thanks

PurpleBeast94

that is weird, I'd almost think head gasket related since it's the most likely thing to affect both the cooling system, and oil pressure.

I wouldn't go and change the head gasket without looking into other possibilities first.

Let us know your discovery

that is weird, I'd almost think head gasket related since it's the most likely thing to affect both the cooling system, and oil pressure.

I wouldn't go and change the head gasket without looking into other possibilities first.

Let us know your discovery

would it still be a head gasket thing if i wasnt burning or leaking oil from the head? just wondering.

PurpleBeast94

yes...

The drain plug on my 92 S-10 4x4 Blazer is all the way towards the bottom on the drivers side.

It is plastic and inset just a bit.

One can not see it from the top, but if you reach down it there it will feel sort of like a plug at first, but if you feel around with your fingers you will find the flat piece for screwing it out, I had to turn mine about 4 turns or so to get it competely open day before yesterday when I was flushing my cooling system out.

And it did not turn very easy either, pretty tight, plus it is hard to get a good grop on it.

If you suspect the head gasket first do a compression test.