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The next issue is no heat. Two things I noticed. A Leak in the radiator and the heater hoses are not hot one is warm and one not so much. 

Seems like a clogged heater core or a heater control valve. Not sure where the valve is located ....waiting for the shop manual...

The blower is working however I don't get hot air blowing out the vents......The defrost seems to be working just fine...

Where is the heater control valve located.?

There is no heat blowing out the dash vents. Does this indicate a problem with the control vents/ blend door?

Any help would be appreciated.

 Thank you

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Hi - I have the same car.  It too, put out no heat when I got it.  I replaced the blend door motor and it began putting out heat.  Although weak.

I also suspected a clogged heater core.  I did some work on it recently and took the opportunity to flush the entire system including the heater core.  I ran a garden hose through it in both directions and had good flow.  I tapped the garden hose into the heater hoses on the passenger side of the engine under the coolant reservoir.  So I think I would have been passing water through any control valve also.

I have not located a control valve.  Curious to see what turns up in this thread.

There is what seems to be, a restrictor in the upper hose.  That is where I tapped in on that hose.  It just has a smaller diameter opening it.  I assume its job is to keep water in the core for a bit to heat things up.  That restrictor has an arrow on it.  Out of curiosity, I have flipped it both ways, even though it didn't make a lot of sense.  No diff either way.

End result is no change.  But I have found that if I put the fan on low auto it gives the heater core time to collect a bit more heat before the blower blows it away.  After a while I put it back on full auto and 20 minutes into a drive it is comfortable.

I will say it is critical to burp that cooling system and to keep it full.  Make sure you have done that.  Burp it using that little valve on the thermostat housing.  You will also have better luck getting all the air out if you raise the front end.  I know, sounds lame but it makes a difference.  Ramps are good enough.  Don't let that little valve leak coolant without stuffing rags around it.  It will run right down to your distributor and that is not a place you want to be headed to next.  Been there, done that.  Rough job.

I am hoping this thread produces info on a control valve.  I have even heard there isn't one.

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Thank you sir for that good information .....

 I have lots to do here......This is a really nice car .... so i need to do whats right to make it close to perfect. 

 I hope to post pictures and a complete DIY procedure. 

 Is the blend door motor easily accessible? and is a replacement available?  

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If I remember correctly it is behind the glove box.  Not too bad to get to.  If I remember correctly, I took the glove box out to make it easier.  That was 7 years ago so...  I got it at Advance Auto.  It was in stock.  $134.00 if I remember right.

I just wobbled along with weak heat (it isn't my daily driver) until I tore it apart last October to replace the distributor, tune it up and take care of a slew of smaller issues.

The heat was better after I put it back together but still not what I would call "good".  I attribute that small improvement to burping the system while the front end was still in the air.  It is the only thing that was different after trying the heater core flush for the 1st time about a year before that.

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If you ever head into the distributor look up this thread here.  1995 Fleetwood Brougham Light Throttle Stumble .

Way too much info there and I have not followed through with my promise to document it all.  There are a few dicey areas.  Save it for recreational reading.  LOL.  PM me if you do ever go there.  I can fill in some of that missing info for you.

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Oh ....OK that dont sound too bad...

Im about ready to click the rock auto button .... Ill add one to the list.

 Yes Im doing the cap rotor and water pump as well ........I cant figure out why GM decided to put that distributor there...

 I Know my town car needed to be burped as well. Good tip raising up the front end BTW.

 Thank you so much for that info ...this is my first GM car so Im still learning...

 

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When you have that distributor cap off check the shaft for lateral play.  Mine was shot.  But it didn't matter because I already planned to just replace everything.  I had no interest in having to go back in there.

If you need to pull the hub for the harmonic balancer save yourself some risk and use a puller that uses a pin that reaches into the crankshaft and bottoms out beyond the threads in the bolt hole.

I didn't have one of those so rented it from Advance Auto.  $128.00 for 45 days and you get 100% of that back.

That hub is really on there tight, probably because it is not keyed.  I actually went through 2 pullers because the threads gave out on the first one!  I was glad I didn't blow off the cautions I had heard and just used a bolt in the crankshaft to push against.  

If you do just replace the cap and rotor, you won't need to remove that hub.  Just the wheel part.

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Ok .... I pulled the glove box ..... The blend door is working.

One less item to order....

 I dont suspect any major issues the car only has 60000mi Im sure the plug wire leads are degraded....so replacement is in order.

Great Info ...Thank You ..

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Weak heat?  

I bet the heater core is clogged with the GM coolant sealer tabs.

I just went thru this last year when I got my 93 Deville.

I replaced the core and its clogged again!

Sure,  I could flush it but its 0 here in frozen NY so I will just suffer with it for the rest of  the winter

and either flush it or replace the heater core again!

Maybe your core is behind the glove box like my Deville but not sure.

I BET THAT THE problem since you checked your temp door acuator.

Your car prob. uses the same 3 way "tee" restrictor instead of a actual vac. controlled valve.

Edited by sonjaab

93 DeVille-13 Chevy Impala

72 GTO - 77 Triumph Bonneville

84 Z-28

Syracuse NY

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BTW:  Heat should NOT blow out the dash vents only when the a/c mode is selected will air

come out the dash vents.  Also depending on what temp is selected and warm a/c air will blow out the dash vents.

Heat/defrost mode air will only come out the defrost vent or floor.

Thats the way my Deville works so your Fleet should be the same.


93 DeVille-13 Chevy Impala

72 GTO - 77 Triumph Bonneville

84 Z-28

Syracuse NY

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Thanks SonJAab ... I did not know that ...... Im sure the door actuator is Ok now that you confirms how it works ...great info ...

 Thank You 

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No prob.!

Another thing to mention is if that 3 way "tee" is installed in-correctly you will also have weak heat.

It seems one of the tee ends is restricted in some way to reduce the water flow.

Check to see if your tee is the original.  Look at the hose clamps.  prob. if they are the new

worm/screw clamps its been replaced.

Did u try to flush the core?

Sorry i dont have pics to post cuz i got a new laptop and they arent on it yet.

Check my old heater core post for pics of my Deville install.

Your Fleet may be similar!

 


93 DeVille-13 Chevy Impala

72 GTO - 77 Triumph Bonneville

84 Z-28

Syracuse NY

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Heres a link to my Deville heater core flush and pics of the  3 way "tee":

 

 


93 DeVille-13 Chevy Impala

72 GTO - 77 Triumph Bonneville

84 Z-28

Syracuse NY

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