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Oldsmobile/Buick Repair/AC system 1987 3.8 cutlass

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Question
QUESTION: I switched my AC to defrost one day and then when I went to put it back to AC max it never blew out of the main vents seems like it's stick on defrost is there a hose or relay I have to check

ANSWER: HI ALEX, NO I AM SORRY BUT THERE IS NOT RELAY. THIS HAS TO DO WITH THE DOOR GOING TO THE VENTS THAT CONTROLLER VACUUM SOLENOIDS ON THE DEGROST DOOR OR THE VENT DOOR.. BEING THAT THIS CAR IS OLDER CK FOR A VACUUM LINE OUT BY THE ENGINE AREA BY THE FIREWALL AND SEE IF YOU FIND A VACUUM LINE THAT MAYBE BROKEN OR SPLT..REPAIR THIS IF YOU FIND IT, THIS WILL ALLOW VACUUM TO OPEN THE VENT DOOR UNDER YOUR DASH..THERE ALSO MAYBE A VACUUM CANISTOR CK THIS FOR VACUUM TO IT AS WELL,YOU WILL FIND THIS UNDER THE HOOD BY THE FIREWALL AREA. [BIG BLACK 4 INCHES ROUND PLASTIC]  THE VACUUM LINE YOU ARE LOOKING FOR IS ABOUT 1/4" ROUND. IF ALL VACUUM LINES ARE OK YOU MAY HAVE A BAD DOOR SOLENOID UNDER THE DASH NOT OPENING OR CLOSING...CK REAL CAREFULL FOR ANY BROKEN VACUUM LINES OUT BY THE ENGINE AREA FIRST...WHEN RUNNING DO YOU HEAR ANY AIR LEAKING INSIDE THE DASH AREA..IF SO YOU HAVE A VACUUM LEAK INSIDE THE DASH AREA...LET TME KNOW HOW THIS GOES AND GOOD LUCK,,TOM..

---------- FOLLOW-UP ----------

canister
canister  
QUESTION: thanks for the response i before i seen this reply i took out the climate control and all the vacuums were disconnected, i put them back together but also since you mentioned a canister....there was a canister by the blower witch i have no idea what is called if you have any idea what that is it would really help me no one seems to know what it is called my uncle says it controls the vents.... its funny you mentioned it let me give you the only numbers it has on from factory (100018660) napa says those were gm part number it has one vacuum in and one out witch goes into the car, for the time being i put it direct and now the vents kind of closed but air is still coming out of the engine bay where  the heater hose come in thanks again for you help never actually thought this would work

Answer
HI ALEX, YES THIS IS THE VACUUM CANISTER THAT I WAS TALKING ABOUT..THIS IS A GM # AND THE PART IS CALLED JUST WHAT I SAID. YOU COULD CALL UP YOUR GM DEALER AND HAVE THEM RUN THIS #,BUT I HAVE ALWAYS HEARD THIS [CALLED AS ABOVE..]YOUR UNCLE IS CORRECT, WHAT THIS DOES IS IT STORES VACUUM AND KEEPS IT THERE UNTILL THE DEFROSTER OR VENT MODE IS PUSHED. THE VACUUM DASH POT IN THE DASH NEEDS ALOT OF VACUUM TO MOVE THESE DOORS TO THE OPEN AND CLOSED POSTION..MORE THEN LIKELY THE CANISTER IS OK,THEY DO NOT GO BAD UNLESS THEY ARE CRACKED AND LOOSING VACUUM...THE MOSE COMMON PROBLEM IS THE VACUUM LINE GOING TO THIS BREAKS OFF OR SPLITS LOOSING THE VACUUM TO IT, OR THE VACUUM LINE GOING INTO THE DASH BREAKS...ONCE YOU HOOK THIS UP JUST MAKE SURE IT IS GETTING A GOOD SUPPLY OF VACUUM AND THERE IS A GOOD SUPPLY COMING OUT OF IT AS WELL. I HAVE ONLY SEEN ONE OF THESE THINGS PLUG IN 35 YEARS..THE LAST POSSIBLE PROBLEM IS THE VACUUM DASH POT UNDER THE DASH IS BAD NOT HOLDING VACUUM. BUT USUALLY IF THIS IS THE CASE WHEN THE CAR IS RUNNING YOU WILL HEAR A AIR LEAK ALL THE TIME FROM UNDER THE DASH. THIS IS VACUUM LEAKING OUT. SO CK THIS OUT AND IT SOUNDS LIKE THIS WAS OR IS YOUR PROBLEM..GOOD LUCK TO YOU,,TOM..  

Oldsmobile/Buick Repair

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TOM SHEETS

Expertise

Can answer all questions pertaining to mechanics of GM cars from 1965 to present. I will answer questions from 6:00 am to 10 pm est.. I will not take diesel or paint questions. If this olds and buick section is maxed out you can get to me in the chevrolet section...

Experience

I have 30 plus years experience in servicing these cars. I can answer questions on carburetor, fuel injection,ignition systems, suspension, brakes and abs, cooling systems,a/c and heater,manual transmissions, rear differential and electrical system,charing system and battery. I am a Master ASE certified mechanic in all 8 categories: - Brakes - Heating and Air Conditioning - Automatic transmission - Clutches and Transaxle - Engine performance - Engine repair - Electrical - Steering and suspension I am certified for NYS inspection and clean air insp.

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ASE

Education/Credentials
I am a Master ASE certified mechanic in all 8 categories (see above) I am an Air Conditioning/Freon recycling specialist with ASE. I have at least 4 years of technical training and many hours of continuing education.

Past/Present Clients
many customers in our busy shop for the past 30 plus years

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