QuestionQUESTION: My 2003 z71 Chevy Tahoe ac is blowing warm air. Before the heat will work in the winter the engine has to get warm and then it kicks on and works great. However the ac is blowing warm air. Any advise? What the problem could be? Can I just recharge it and see if it helps? I had someone do a dye test and see if there was a leak but I don't know if he really did it and just charged me for the test. He said it was not leaking and thought it might need a compressor. He has a side business and was rushed so Im not so sure he really looked into the problem.
ANSWER: HI KARA, LETS START OFF WITH THE HEAT ISSUE, THIS MAYBE NORMAL DEPENDING ON HOW LONG IT HAS TO RUN TO GET WARMED UP. IF I YOU YOU THIS FALL TIME I WOULD INSTALL A NEW THERMOSTAT AND FLUSH THE COOLING SYSTEM, [INCLUDING THE HEATER CORE.] THIS SHOULD GET YOU GOOD HEAT.. THIS WILL HAVE NO EFFECT ON YOUR A/C SYSTEM. NOW WE WILL GET TO THAT PROBLEM. DOES THIS HAVE REAR A/C ??? IF SO, MORE THEN LIKELY THE LINES FROM THE FRONT TO REAR ALONG THE FRAME RAIL ARE LEAKING VERY, VERY COMMON. NEXT IS THE REAR EVAPORATOR... IF YOUR TRUCK DOES NOT HAVE REAR A/C. THIS MAKES THING EASIER.. BY PUTTING A DYE IN THE SYSTEM THE TECH SHOULD BE ABLE TO LOCATE A LEAK,[FRONT OR REAR] UNLESS INTERNAL. IF YOU WANT TO CK TO SEE IF THE TECH PUT DYE IN THE SYSTEM,REMOVE A HIGH OR LOW SIDE CHARGE LINE CAP [BLUE IN COLOR] TAKE A SMALL SCREW DRIVER AND PUSH DOWN ON THE VALVE FOR A 2 SECONDS OR SO, THIS WILL RELEASE SOME FREON. IF THERE IS DYE IN THE SYSTEM THIS AREA WHERE THE FREON CAME OUT WILL TURN LIGHT GREEN,THIS IS THE DYE. IF WHEN YOU PUSH DOWN ON THIS VALVE AND NO FREON COMES OUT, THE SYSTEM IS FLAT EMPTY.. HOWEVER IF THE SYSTEM WAS OK ALL LAST YEAR AND NOW IT BLOWS WARM AIR. IT IS POSSIBLE THAT IT IS JUST LOW ON FREON. I WOULD TAKE IT TO A PLACE THAT DOES WORK ON ALOT OF A/C. THEY WILL BE ABLE TO TELL YOU IF THE SYSTEM IS LOW OR EMPTY...[MY RULE IS] IF SYSTEM IS JUST LOW ON FREON CHARGE IT, SEE HOW LONG IT LAST..IF EMPTY,PARTIALLY CHARGE IT AND FIND THE LEAK.. THERE ARE MANY POSSIBLE CAUSES FOR A LEAK>>> SUCH AS,LINES, COMPRESSOR, CONDENSOR AND FRONT EVAPORATOR, [IN THE DASH] THEY WILL HAVE TO RULE OUT NO EXTERNAL LEAKS FIRST AND IF NONE FOUND THE ONLY PLACE LEFT IS THE EVAPORATOR IN THE DASH.. THIS IS BIG $$$$ TO REPLACE. YOU DID NOT TELL ME HOW LONG AGO THIS WAS CHARGED,OR WHEN THE DYE WAS INSTALLED. SO YOU WILL HAVE TO GO ON WHAT I SAID ABOVE..I HOPE THIS HELPS YOU AND IF YOU NEED MORE INFO GET BACK TO ME.. PLEASE WHEN YOU LEAVE THIS SITE WOULD YOU RATE MY ANSWER. GOOD OR BAD. THANK YOU VERY MUCH,,,TOM...
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QUESTION: Thanks so much Tom. Let me give you some more info.
The truck does have a rear unit. It has it's own set of problems.
I am ok if we just use the front unit. The truck has 120k miles
And is 9 years old. But it looks great and is in great shape.
The guy that "apparently" did the dye test did it last August.
When I test it will I still see dye if he did do the test since
It was so long ago?
Can we just add freon and see if it works or will it harm it if it is not needed?
Thanks
AnswerHI KARA, I WILL ASSUME THE FREON LINES GOING TO THE REAR UNIT ARE BLOCKED OFF,CORRECT.. IF THEY ARE NOT BLOCKED OFF[SEALED SHUT] YOU WILL LOSE FREON IF YOU USE IT OR NOT...SO MAKE SURE IT IS BLOCKED OFF. YES,YOU WILL SEE THE DYE THAT HE INSTALLED IN THE SYSTEM LAST YEAR,PROVIDING THERE IS FREON IN THE SYSTEM TO PUSH IT OUT THROUGH THE VALVE..DO NOT GET YOUR FACE BY THIS WHEN YOU TEST IT. MAY WANT TO WEAR GLOVES, A LITTLE OILY AS WELL. IT NEVER GOES AWAY...IT IS LIKE A BAD DREAM,ON AND ON AND ON..LET ME KNOW HOW THIS WORKS OUT FOR YOU AND GOOD LUCK ,,TOM.
