a/c not cooling

cdmm151 · April 11, 2005

My a/c is an aoutomatic style on a 2005 GMC crewcab. The a/c only blows 50 going downthe highway in the recirculation mode and turn down as far as it will go. Are there any TSB's I need to know before I take it in? also the trany cluncks from to time to time. What can they do for that? It seems like it is very loose.

Thanks

71GMC_3/4T · April 11, 2005

For the tranny, I just told the service advisor that it clunked once in a while when starting after coming to a rolling stop. They put a new nickel plated yoke in, no questions asked. I figured I'd have to argue with them for a while about it, but they surprised me.

GM-Tech · April 11, 2005

No TSB's on the a/c. 50 is actually within specs.

snoman · April 11, 2005

No TSB's on the a/c. 50 is actually within specs.

<{POST_SNAPBACK}>

Oh how I miss the old R-12 systems sometimes. I do not plan to ever convert my 89 burb to R134a. I have a small stock of R12 for it too.

GM-Tech · April 11, 2005

I have a small stock of R12 for it too.

Better hang on to it. R12 is worth it's weight in gold!

snoman · April 11, 2005

I have a small stock of R12 for it too.

Better hang on to it. R12 is worth it's weight in gold!

<{POST_SNAPBACK}>

Yes I have seen it go for $50 a can and more. The sad part is I can remeber when in the early 90's before the big switch over I could have bought all I wanted by the case for about 69 cents a can. I wish I had bought a truck load of it then. I even have a new unopened quart of geninue GM R12 compressor oil too. I keep my R12 in a big deep freezer to minimize any possible leakage from presure. I believe I have about 12 cans or so.

cdmm151 · April 12, 2005

Found out what my problem is. It is me. The automatic a/c doesn't work the same as my 2002 suburban with auto air. The 2002 when in the auto mode it will blow hard and 40* until it get to the temp you have it set at,then reduces the fan but continues to blow cold but at alower speed. The 2005 with auto air it will only blow hard and 40 when set at 60*. If set at 68-70 it will blow slower and at a higher temp. I quess it will take time to get used to.

As for the clunck I will have to get it checked.

GM-Tech · April 12, 2005

You're 2002 wasn't operating properly then, because it also adjusts the speed and temp to maintain the desired temperature when in auto mode. Here's from the "Description and Operation" of temperature control on a 2002 Suburban. I've put the part about regulating the temperature door in bold...

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The HVAC control module will perform the following routines to maintain the desired air temperature:

• Monitor the following sensors:

- The inside air temperature sensor

- The ambient air temperature sensor

- The upper air temperature sensor if cool air is required

- The lower air temperature sensor if warm air required

- The sunload sensor

• Regulate blower motor speed.

• Position the air temperature actuator

• Position the mode actuator

• Position the recirculation actuator