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Buick LeSabre, Electrical, Sedan
#158 of 188 Re: 1997 Buick LeSabre...PLEASE Help...Is It A Head Gasket? [photokid777]
Jul 16, 2011 (3:35 pm)
Most likely it's a leak through the EGR tube inside the upper intake manifold. The hot gases deteriorate the plastic and right next to that is the water going through the upper intake to the throttle body to warm it in winter. The coolant leaks into the incoming air. If you take off the throttle body and or the honey comb on the end, open the throttle plate wide and look inside you'll see coolant on the bottom of the upper intake area. This gets sucked into the cylinders causing a miss.
The lower intake gaskets, under the metal lower, also can leak. This water goes into the cylinder intake more directly. Often when the car isparked under pressure, the water leaks into one cylinder causing hydrolock and the engine won't turn over.
Head gasket problems are very rare short of overheating the engine to a degree you couldn't miss it happening.
The coolant from either leak is getting into the oil. This will acidify and detriorate the bearings on the crankshaft causing failure.
If your upper intake has been replaced, it will either have no circles on top or the circles will be marked for date later than 1996/1997. One of the circles is the year. Aftermarket brands don't have the circles like GM.
The current oil needs to be drained quickly and replaced, even with cheapest generic oil while the engine is getting in to be worked on. Then drain and replace again after 50-100 miles even the fresh oil put in when the intake parts are replaced.
Be sure to use metal framed gaskets for the lower intake. ineedparts.com is a source for a good upper intake. Rockauto.com. If you are doing it yourself.
#159 of 188 1999 Buick LeSabre Air Conditioning fun
Jul 23, 2011 (5:07 pm)
#160 of 188 1999 Buick LeSabre Air Conditioning fun
Jul 11, 2011 (11:37 am)
So when I first start my car, the AC blows only on window and floor, but not Mid level. No-matter what I do, I cannot get it to change. However, after the car has been running for about 15 minutes, it will gradually change on it's own to blow through the mid level vents. The air is also cold (so that doesn't seem to be an issue).
Any ideas? I have read that it could be the vent or air door actuator....but could also be a vacuum leak somewhere (although that may make less sense)
#161 of 188 Re: 1999 Buick LeSabre Air Conditioning fun [88fenderstrat]
Jul 11, 2011 (11:50 am)
Try reading in that thread. I'll see if I can find a Bonneville topic where this has been discussed.
You've either lost vacuum to the programmer box from the motor side or the little distributor plastic connector on the corner of the programmer box is collapsing. Usually they collapse as the car runs longer instead of what you are getting.
When you turn off the motor and leave key ON, can you hear the vacuum motors move under the dash with the left over vacuum when you press different air flow buttons on the dash control?
Here is a link to Bonneville topic with same problem:
#162 of 188 Re: 1999 Buick LeSabre Air Conditioning fun [imidazol97]
Jul 11, 2011 (12:10 pm)
Thanks for the info. I will read through and check out the other discussions. I will also see if I can hear vacuum motors moving after I cut the engine.
Very strange indeed because there is no discernible loss of power (engine not running rough...like you sometimes see in a vacuum leak), and the problem seems to get better (i.e., air comes out of the mid level) if I run the engine long enough.
Back with you shortly.
#163 of 188 Re: 1999 Buick LeSabre Air Conditioning fun [88fenderstrat]
Jul 11, 2011 (12:25 pm)
If you have enough vacuum to move the motors for 20-30 seconds after engine shutoff, then your underhood llines are okay. It's the connector for the programmer for the 4-5 lines.
If you don't have much vacuum, check at engine end next to large brake booster hose for rotted rubber end for the plastic vacuum line. Check under Relay Center cover down in bundle of wires for the T connection and ahead where there's a vacuum one-way valve. Check the storage tank under the right front fender behind headlight.
This is the piece on the corner of programmer box that needs to be bypassed--at least the blue line to the diaphragm for the door for the defroster to make the air come out the dash vents.
#164 of 188 Re: 1999 Buick LeSabre Air Conditioning fun [imidazol97]
Jul 11, 2011 (12:37 pm)
Thanks! I will let you know how it turns out.
Jul 13, 2011 (4:17 pm)
I am working on a 95 LaSabre that seems to be leaking condensate from under the dash. What causes this and how do I fix it? Thanks!
#166 of 188 Re: Leak under dash [grizleebear]
Jul 13, 2011 (4:25 pm)
Almost always that's due to the drain tube being stopped up. Get under the car on the right side behind the wheel and then look at the lower part of the firewall just slightly to the right of center. You should find a 4-5 inch long tube that is stopped up with muck or pollen or dirt.
Stick something up into the tube and be sure you're not under the tube while you do that. Usually a lot of water will come out.
When the AC has been running on humid days and the car is parked, is there a drip of condensation that comes out the bottom of the firewall? If not, then the AC drain is stopped up.
Rarely someone found a leak around another part letting water into the passenger compartment onto the floor. Has there been lots of rain? Does the car have a sunroof?
#167 of 188 Re: 1999 Buick LeSabre Air Conditioning fun [88fenderstrat]
Jul 23, 2011 (4:33 pm)
Here is the end of the story. I traced the lines back to the connector for the programmer. When I too the connector out, the nipples were not cracked, etc. However, when I plugged it back in, the air conditioner started to function properly. Go figure. So, I took it out again and looked more closely. The nipples were soft, and I have come to the conclusion that one or more of them were collapsing. So, I cut all of the lines, spliced them, and bypassed the connector altogether. The a/c vents work beautifully now...no problems.
Thanks again for your help. The photo was very helpful as well.