Last post on Nov 19, 2013 at 7:01 AM
You are in the Buick LeSabre
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Buick LeSabre, Heating / Cooling
#269 of 278 Re: OVERHEATING ON A 2002 LESABRE [stresd_damzel2]
Jun 28, 2013 (6:46 am)
Take a look at the color of the engine oil on the dipstick. If it's a brown, milkshake color, your coolant may be getting into the engine oil. That's fatal if it has gone on for a while.
I don't understand what the mechanic did. But the most common problem will be the gasket under the metal lower intake manifold and the heads has deteriorated and is allowing a leak into the engine air intake and the oil pan. That may explain the stalling because the coolant causes misfiring in the cylinders.
A second problem area might be the intake manifold that's plastic where it meets with the metal throttle body that controls the air intake and volume. That gasket can leak.
A third area might be the EGR internal port which is hard plastic has deteriorated with heat--not as likely after 1999.
A fourth problem might be not the above but that the coolant is goopy if someone added regular green antifreeze to the original orange DexCool. That may be blocking some of the coolant flow through the radiator.
You need to find a good mechanic who knows these cars. A dealer may be your best bet for an analysis of what the problem is, despite their higher cost. You may be spending money as well as time with damage occurring at a poor local mechanic.
#270 of 278 Re: 94 Lesabre A/C blowing out defroster vent [clearlake]
Jul 08, 2013 (4:41 pm)
Is there a chqnce you still have these pictures and how u fixed this issue. This is the exact issue i am having with my 1999 buick lesabre. Thanks for ur help.
#271 of 278 replaced battery now a/c doesn't work
Jul 17, 2013 (12:19 pm)
I had to replace my battery and now my ac is not working. Air will only blow through the defroster and it doesn't get very cold. I have had my car looked at and was told that my a/c unit is working fine and it is probably an actuator but now sure how to decide which actuator to buy. I have automatic ac with temperature display but not dual controls. Please help...
#272 of 278 Re: replaced battery now a/c doesn't work [lmcclenton]
Jul 17, 2013 (4:50 pm)
What year is your leSabre?
When there is no vacuum, the system should go to defroster for safety.
But on 1999 and prior, there also is a problem with operation of the actuator for the door that blocks the defroster and makes air come out the dash vent.
#273 of 278 2002 lesaber temp control
Aug 15, 2013 (8:43 am)
2002 lesaber heat blows cold unless temp set at max 90 it is a limited w/dual control
#274 of 278 2002 lesaber temp control
Aug 15, 2013 (8:50 am)
where is temp sensor for heating system dual control digital system
#275 of 278 99 Buick Lesabre AC doesn't blow through vents
Sep 22, 2013 (6:57 am)
My 99 Buick Lesabre AC doesn't blow through vents. It only blows out the defrost and floor. It works on all fan speeds. No matter what air flow position I select on the Ac head unit it will only blow out the defrost and floor. I have done a lot of reading on this problem and thought several times I was close to solving the problem with disappointing results. Here is what I have done to this point. I have replaced the AC head unit twice, what they call the Air Mix Actuator and the AC programmer. (All parts from local salvage yard). The vacuum line leading in from the fire wall has been vacuum tested. When I first turn my key on the 2 levers of the doors move to the right and then back to the left. If I change my temperature on the head unit to warm then the 2 levers move to the right and I have heat. So I am assuming the doors are functioning properly(??) But like I said no matter what air flow selection I choose on the AC head unit I only get air flow from the defrost and floor. Nothing comes out the vents. I am at a loss. Can someone please help? FYI... I had the same problem on a 94 Lesabre and I change the head unit and the problem was solved for about a year. Then it would from time to time just blow out the defrost and floor. You could just be driving down the road and it would switch back to the vents. Makes me wonder if the head unit was the whole culprit on the 94 or not? I've sold the 94 so it is not an issue now. I thought I would mention my 94 problem just so you know my frustration with Lesabre AC issues. Once again CAN someone please help me?
#276 of 278 Re: 99 Buick Lesabre AC doesn't blow through vents [eagleman60]
Sep 22, 2013 (8:14 am)
If the other vacuum controls move correctly when set on floor/windshield, and you are sure you have correct vacuum with no leaks at the storage tank behind the headlight, and you can move a line off the floor control diaphragm on the driver side and put it on the diaphragm for the upper doors (blue line), then you have a problem with this sucking shut.
You can cut it off from the vacuum lines and slide vacuum line over the tubes (Oreilly's sells it by the foot or in boxes). Connect the correct color from the inner part of the programmer box to the color on the outside--they are not all the same.
Programmer sits on corner of heater box.
You can reach all this by removing the sound shield under the dash and removing the glovebox door at the hinge.
#277 of 278 97 Buick Lesabre blows cold air, until have been driving for extended time
Nov 19, 2013 (6:12 am)
i have 97 buick lesabre. last winter, the heater worked awesome, not a problem. so far this winter, the heater blows cold air, even after letting the car run for 10-15 minutes. the airflow will start going to warm after driving it for a little bit, but not much (in a 30mph zone). hopping on the freeway, the heater works just fine, but when sitting at a stop sign, or a stop light, it starts blowing cold again. any ideas?
#278 of 278 Re: 97 Buick Lesabre blows cold air, until have been driving for extended time [grizzlymanbear]
Nov 19, 2013 (7:01 am)
I assume it's the manual control heater and the actuator for the temperature is working right. See last paragraph.
Your car may have a thermostat that is not closing completely when cold or opening too early. After 5 minutes with a cold engine, the upper hose should still be cold while the heater hoses are warm and hot. You should be able to feel the thermostat open when the coolant gets to 195 as shown on the dash gauge, by the hot water coming into the upper hose in slow spurts and warming it some. The thermostat may open slowly and just the bottom of the hose gets warm at first. After 10 minutes or so, the upper hose should be too hot to hold for more than a few seconds unless your hands are really toughened up from being used to hot things.
You might have low coolant level in the radiator--have to take the cap off when cool to see if there is coolant up to the cap level. Can NOT check just the level in the plastic reservoir. But that usually has a couple other symptoms.
Your coolant may be old and clogging the heater core lowering the flow rate. If you are careful you can check the temperature of the two lines into the firewall behind the engine. Be careful of the moving belt at the alternator. After the engine and car have been warmed up, with the heater blower on high the temperature of the one metal tube should be some cooler than the other one. But both should be hot. If you turn the fan speed on low and retest, the tubes should be nearer in temp due to the water in the heater core not being cooled as much by the air.
Having someone run the engine at 1500 rpm or more for a minute before testing should improve the temperature of the out hose making it closer to the input temperature.
If the flow in the radiator is partly blocked, you can have the cooling system cleaned with a cleaner to try to pick up some of the gunk in the heater. The better solution is to take off the rubber tubes at the engine end and try to flush the heater core with light water pressure in both directions.
A remote possibility is a water pump.
The electric actuator on top of the heater box pushes a white plastic arm and a metal rod to move the temperature blend door. That actuator may be slipping and not pushing the rod all the way to the hot side. You can take off 3 screws and a couple taps on the firewall to remove the plastic panel under the dash. Take off the glovebox door for easier access--7 screws across the bottom hinge. You can try to move the actuator with a gentle push. If it moves, the inside axle is slipping due to a cracked gear. OR you can watch it move as you change the temp setting with the key ON to see which way it goes for HOT, and then try to push it further and see if you get more heater with the engine running in that position. If the actuator is going full hot, with a hot engine running at 40 or more the air coming out the vents should be so hot you can't hold your hands there.