No heat after car ran hot.

[jmpSHO]

The little hose that connects to the throttle body split while on the highway. I didn't over heat the car, unless my temp gauge is wrong, but it did reach above the N a few times as I was trying to get it back to my garage. It never hit the red at all. I replaced the hose and filled the radiator and overflow and now I have no heat. Besides the no heat everything else is normal, it runs fine and reaches normal operating temp but I have no heat. By the way it is an ATX with 290K. The radiator and heater core are only about 2 years old and I just had it flushed at the begining of the year.

 

[Shoaz]

There may still be air in the system. Try to burp it/purge it and see if the heat comes back.

 

[shonuffmine]

i concur with the air bubble theory too, my 3.4 grand prix did the same thing. i ended up putting a back flush T by the heater core to burp it(high point in the system)

 

[sperold]

Your thermostat is stuck wide open. You have no heat at all if you remove a thermostat. So sticking wide open is the near equivalent. Change the thermostat even if it corrects itself in the next little while.

 

[frosho]

Your thermostat is stuck wide open. You have no heat at all if you remove a thermostat. So sticking wide open is the near equivalent. Change the thermostat even if it corrects itself in the next little while.

Considering the fact that he lost a bunch of coolant, it's more likely just air in the system.

 

[jmpSHO]

Considering the fact that he lost a bunch of coolant, it's more likely just air in the system.

That's what I am thinking too. I'm going to try and get the air out today.

 

[Racer X]

I'm going to go with air.

Even if the thermostat is stuck open, it will eventually get warm enough to generate heat.

 

[jmpSHO]

Well it still has no heat and thermostat is fine, the car reaches normal operating temp no problem and I had heat before the line blew and it ran hot. There was air in the system I am trying to burp is as we speak but there is still no heat at all.

 

[VortecGT]

are the hoses going to the heater core getting hot when the car is up to temp?

 

[jmpSHO]

are the hoses going to the heater core getting hot when the car is up to temp?

Yeah they do get hot after the car warms up.

 

[TopGunnYFZ]

Blend door?

 

[Shoaz]

Blend door?

That's my thought. Or something just came loose, or the EATC crapped out or something.

If the fan works and there's hot water going to the heater core the BDA is the next likely culprit. There have been some trick mods published around on how to get the BDA to "heat" if it has failed rather than yank the whole dash.

 

[jmpSHO]

It sucks I have had my dash out twice in the past 2 years and I'm not looking forward to doing again. It's weird because everything worked fine before the line blew and it ran hot getting it home. I have another EATC so I might try that first.

 

[jmpSHO]

If the BDA was bad wouldn't the EATC show a code during the diagnostic test?

 

[Shoaz]

If the BDA was bad wouldn't the EATC show a code during the diagnostic test?

There is a test that will show a code when the BDA fails.

Bottom line is that if the heater hoses are hot there's likely hot water getting to the heater core. Then it's just an issue of getting the air through, which is either a fan or blend door problem, or something stuck in there. Either way, it may not be too tough (but probably tedious) to diagnose.

 

[jmpSHO]

So for the third time I attempted to bleed my coolant system and I noticed that one of the hoses from the heater core are not getting as hot and I might have mistaken it before as getting hot as engine heat. So I am thinking maybe a blocked heater core but I still can't see how that happened.

 

[Marccus]

Well, to put my two cents in. I have a John Deere coolant eye on heater hose outlet. This is a thick walled clear hard plastic tube with a clear plastic dip leg with a valve on the end. Small particles settle out in the dip tube and you can drain them.

Since it is clear, I can readily detect if there is air in the system. When I change the entire cooling system it takes me a LONG time to finally get all the air out and finally get flow through the heater hoses. Up until flow starts through heater hoses I can see the air pocket in the horizontal section of plastic tubing and no flow.

When I had he problem I kept telling myself it wasn't air, but it was! It just took a long time to get it all purged.

Note that I've only seen this when I do a complete coolant change or have lost a significant amount of coolant from a broken hose or something else.

I've used several suggestions by people on this forum to get the air out and eventually they all helped - Jacking up the passenger side to make the radiator cap the highest point in the system.

While filling the system and continuing to fill it after I start the car and before installing the radiator cap, I squeeze the upper radiator hose to burp air out of he system. When you do this when air is in the system, you will see the level in the radiator go down, and then you can add more coolant, keep sqeezing and adding coolant every time the level drops until squeezing doesn't seem to help anymore. This will minimize the amount of trapped air in the system.

Good luck.

 

[jmpSHO]

Well today I finally got heat. I pulled the heater core hoses off and used my compressor to blow air through it and a little bit off gunk came out I don't think it was enough to block it but after putting it all back together and bleeding the system again I finally have heat.