2004 GMC Sierra AC question

[mpr3369]

I have a 2004 GMC Sierra Z71 with a 5.3. The ac doesn't get very cold and if I get on it it starts blowing warm then when u get to speed it starts cooling off again. Also if your sitting and idling it warms up again. I was thinking about changing the accumulator and orifice tube and vac it down and recharge it. But my friend told me he had that problem with a newer nissan xterra and it ended up bein a thermatic switch. Does anyone know what the problem could be? Thanks for your help!

 

[Molson02536]

I have a 2004 GMC Sierra Z71 with a 5.3. The ac doesn't get very cold and if I get on it it starts blowing warm then when u get to speed it starts cooling off again. Also if your sitting and idling it warms up again. I was thinking about changing the accumulator and orifice tube and vac it down and recharge it. But my friend told me he had that problem with a newer nissan xterra and it ended up bein a thermatic switch. Does anyone know what the problem could be? Thanks for your help!

Being a 2004, good chance that it may just be low on R134a. To really know what is wrong, you need to know what the high and low side readings are to your A/C system.

Your high side should be 250 to 300 PSI
Your low side should be 30 to 35 PSI
and your engine steady at 2000 RPM, this should keep your a/c running at 110%.

Try to stay away from the over the counter recharge kits and do not add any stop leak to your a/c system, if your over charge the system. You will have the same issue as your having now, but with a over charged system can cause damage to your Compressor or cause any of your O rings to fail.

Good luck and keep us posted.

 

[mpr3369]

Thanks I'll have my buddy put the gauges on it and check it out. I'll let ya know how it works early next week.