Chevrolet

Ask a Chevy Question, Get an Answer ASAP!

Have your own Chevy question?

8 Chevy Mechanics are Online Now

characters left:

Not a Chevy Question?

Question

2003 suburban
ac pleriodacally blows hot air then goes cold after different times lengths
checy has added a switch a brought freon up to par . still happens they are stumped

Submitted: 1236 days and 20 hours ago.

Category: Chevy

Value: $15

Status: AWAITING CUSTOMER ACTION

Optional Information

Posted by BOBBYSS 1236 days and 20 hours ago.

Answer

Do you have automatic a/c or is it manual?

1236 days and 20 hours ago.

Reply

Reply to BOBBYSS's Post: bobby, i am not sure
i turn it on in flrida and don't ususlly adjust
i would say manual
i do not see any autoclimate contol

Posted by BOBBYSS 1236 days and 20 hours ago.

Answer

Is there any digital read out or just knobs and levers?

1236 days and 20 hours ago.

Reply

Reply to BOBBYSS's Post: bobby
just knobs for fan and temp control
jd

Posted by BOBBYSS 1236 days and 20 hours ago.

Answer

Okay. Does any variable come into play? Does it happen more at a stop, when cruising, when accelerating, or does it not matter?

1236 days and 20 hours ago.

Reply

Reply to BOBBYSS's Post: so far it hasnot mattered
long trips hours at a time okay
somtimes just going to lunch it blows hot air
it also seems to blow hotter than the heater
this heat is superheat !!

nothing i have done ( changing fan selection defrost floor
on off recylce rear front has any effect

1236 days and 19 hours ago.

Reply

Reply to BOBBYSS's Post: bobby, you haven't quit me have you??
john d

Posted by BOBBYSS 1236 days and 17 hours ago.

Answer

No, I'm still here. I am trying to get a better idea so pardon all of the questions. If you have the air on, and it is cold, and then it gets hot, if you leave it on will it get cold again on it's own?

1236 days and 12 hours ago.

Reply

Reply to BOBBYSS's Post: i have not left it on that long
gets too hot in the car

Posted by BOBBYSS 1236 days and 10 hours ago.

Answer

Is there any way for you to see if the a/c compressor is functionig when it gets hot? Do you know where the compressor is?

1236 days and 2 hours ago.

Reply

Reply to BOBBYSS's Post: yes i thought of that also
it cclicks on and off as i turned the ac switch on

Posted by BOBBYSS 1236 days and 1 hours ago.

Answer

Okay, it should. Now what I am wondering is if the compressor is on when the air suddenly gets hot.

1236 days and 1 hours ago.

Reply

Reply to BOBBYSS's Post: bobby, what i have experienced as i go down the highway the ac turns immedialty from cold to hot

Posted by BOBBYSS 1236 days and 1 hours ago.

Answer

The reason I am asking about the compressor is that I am trying to see if this is related directly to the a/c system. You say that the air seems super heated, unlike normal heater air. So I am trying to determine if you are having a break down of one of the main a/c components or a cxomponent inside the vehicle. So this only happens at a time when it is not practical to stop and open the hood?

1236 days and 1 hours ago.

Reply

Reply to BOBBYSS's Post: no it happened in the driveway this past weekend
i checked the compressor , it cycled on andoff as i engaged the switch .

i do not know what else to look for

the dealer appears to be stumped as well
yesterday they let it run several hours but the
problem did not occur

Posted by BOBBYSS 1236 days ago.

Answer

Okay here is what I need for you to check. Hopefully the car will do it sooner than later. When you are looking under the hood, to the left of the motor, there is a cylinder near the firewall. It is probably wrapped in a black insulating material. When the car blows hot air leave the a/c on. On this cyliner there is a line that comes out of the firewall and another line that goes to the compressor. When the a/c is hot, and still on, feel the line that comes out of the cylinder as close to it as possible and see if it is cold. If we can find this out we can go from there.

1235 days and 22 hours ago.

Reply

Reply to BOBBYSS's Post: THANKS I WILL be in the car tomorrow and
see what happens
jd

Posted by BOBBYSS 1235 days and 22 hours ago.

Answer

Let me know as soon as you can.

1235 days and 19 hours ago.

Reply

Reply to BOBBYSS's Post: bobby this transition is instantaneous
is there a valve or swicth that controls a damper for the heater core to direct heat elsewhere

i am thinking this is whre the hear iscoming from

when it goes back t cool or cold it changes in a minute or so

Posted by BOBBYSS 1235 days and 18 hours ago.

Answer

You have one of two things happening. Either your a/c system is letting hot freon to back flow through the system, this is why I wanted you to check that hose for temperature. Or you have a problem with the doors under the dash. I would find the vacuum lines that enter your firewall from the engine. There should be an inline plastic check valve. When you find this I will tell you how to check it.

1235 days and 18 hours ago.

Reply

Reply to BOBBYSS's Post: bobby i think we are getting close
i will gt back to you after lunch tomorrow

thanks

Answer

Okay. Let me know what you find and we will go from there.

Accepts:
Expert:	BOBBYSS
Pos. Feedback:	99.6 %
Answered:	7/6/2006

Technician/Service Advisor

ASE MASTER CERTIFIED, AA DEGREE AUTO/DIESEL TECH. 13YRS. CHEVY EXPER.

Disclaimer: Information in questions, answers, and other posts on this site ("Posts") comes from individual users, not JustAnswer; JustAnswer is not responsible for Posts. Posts are for general information, are not intended to substitute for informed professional advice (medical, legal, veterinary, financial, etc.), or to establish a professional-client relationship. The site and services are provided "as is" with no warranty or representations by JustAnswer regarding the qualifications of Experts. To see what credentials have been verified by a third-party service, please click on the "Verified" symbol in some Experts' profiles. JustAnswer is not intended or designed for EMERGENCY questions which should be directed immediately by telephone or in-person to qualified professionals.

Chevrolet

Have your own Chevy question?

Question

2003 suburban ac pleriodacally blows hot air then goes cold after different times lengths checy has added a switch a brought freon up to par . still happens they are stumped

Optional Information

Answer

Do you have automatic a/c or is it manual?

Reply

Reply to BOBBYSS's Post: bobby, i am not sure i turn it on in flrida and don't ususlly adjust i would say manual i do not see any autoclimate contol

Answer

Is there any digital read out or just knobs and levers?

Reply

Reply to BOBBYSS's Post: bobby just knobs for fan and temp control jd

Answer

Okay. Does any variable come into play? Does it happen more at a stop, when cruising, when accelerating, or does it not matter?

Reply

Reply to BOBBYSS's Post: so far it hasnot mattered long trips hours at a time okay somtimes just going to lunch it blows hot air it also seems to blow hotter than the heater this heat is superheat !! nothing i have done ( changing fan selection defrost floor on off recylce rear front has any effect

Reply

Reply to BOBBYSS's Post: bobby, you haven't quit me have you?? john d

Answer

No, I'm still here. I am trying to get a better idea so pardon all of the questions. If you have the air on, and it is cold, and then it gets hot, if you leave it on will it get cold again on it's own?

Reply

Reply to BOBBYSS's Post: i have not left it on that long gets too hot in the car

Answer

Is there any way for you to see if the a/c compressor is functionig when it gets hot? Do you know where the compressor is?

Reply

Reply to BOBBYSS's Post: yes i thought of that also it cclicks on and off as i turned the ac switch on

Answer

Okay, it should. Now what I am wondering is if the compressor is on when the air suddenly gets hot.

Reply

Reply to BOBBYSS's Post: bobby, what i have experienced as i go down the highway the ac turns immedialty from cold to hot

Answer

Reply

Reply to BOBBYSS's Post: no it happened in the driveway this past weekend i checked the compressor , it cycled on andoff as i engaged the switch . i do not know what else to look for the dealer appears to be stumped as well yesterday they let it run several hours but the problem did not occur

Answer

Reply

Reply to BOBBYSS's Post: THANKS I WILL be in the car tomorrow and see what happens jd

Answer

Let me know as soon as you can.

Reply

Reply to BOBBYSS's Post: bobby this transition is instantaneous is there a valve or swicth that controls a damper for the heater core to direct heat elsewhere i am thinking this is whre the hear iscoming from when it goes back t cool or cold it changes in a minute or so

Answer

Reply

Reply to BOBBYSS's Post: bobby i think we are getting close i will gt back to you after lunch tomorrow thanks

Answer

Okay. Let me know what you find and we will go from there.

Related Chevy Questions

2003 suburban
ac pleriodacally blows hot air then goes cold after different times lengths
checy has added a switch a brought freon up to par . still happens they are stumped

Reply to BOBBYSS's Post: bobby, i am not sure
i turn it on in flrida and don't ususlly adjust
i would say manual
i do not see any autoclimate contol

Reply to BOBBYSS's Post: bobby
just knobs for fan and temp control
jd

Reply to BOBBYSS's Post: bobby, you haven't quit me have you??
john d

Reply to BOBBYSS's Post: i have not left it on that long
gets too hot in the car

Reply to BOBBYSS's Post: yes i thought of that also
it cclicks on and off as i turned the ac switch on

Reply to BOBBYSS's Post: no it happened in the driveway this past weekend
i checked the compressor , it cycled on andoff as i engaged the switch .

i do not know what else to look for

the dealer appears to be stumped as well
yesterday they let it run several hours but the
problem did not occur

Reply to BOBBYSS's Post: THANKS I WILL be in the car tomorrow and
see what happens
jd

Reply to BOBBYSS's Post: bobby this transition is instantaneous
is there a valve or swicth that controls a damper for the heater core to direct heat elsewhere

i am thinking this is whre the hear iscoming from

when it goes back t cool or cold it changes in a minute or so

Reply to BOBBYSS's Post: bobby i think we are getting close
i will gt back to you after lunch tomorrow

thanks