2001 Yukon ac blow warm at idle but cold at speed

[Dvdtactical]

2001 Yukon 5.3 4x4 SLT with rear air and manual controls.

Pressures are at spec. Replaced compressor, R drier, o tube, lines as needed. At start up it blows COLD 36-40F. Head out it blows cold. Stop at store 25 minutes away and it blows really warm. Pressure on low side runs 45-50. Drive home and it blows cold again. Park and idle it stays blowing cold. Guess the truck doesn't like going to town.

 

[Scottydoggs]

the fans coming on?

 

[Fless]

If the electric fan mod hasn't been done, is the fan clutch working correctly?

Are both halves of the fan shroud in place?

 

[Dvdtactical]

My thoughts were leaning to the clutch but it appears to be working. Spins with some resistance.

 

[Dvdtactical]

the fans coming on?

Clutch fan appears to be working. Never replaced, yet.

 

[Scottydoggs]

Clutch fan appears to be working.ver replaced, yet.

ye ol clutch fan, engine off grab a fin, push and pull rad to engine feeling for play. if its got play its bad, if you can just spin it and turns round and round, its bad.

 

[Fless]

There may also be air baffles on either side of the radiator, behind the grill. Make sure they're in place and in good shape.

 

[houstontaylor]

The fan clutch can still have some resistance but be too loose to blow enough air over the radiator. If I remember, an aftermarket fan clutch I tried resulted in too much fan noise so I reverted to an oem fan clutch. Even with a good working fan clutch, there is sometimes not enough air flow at idle to keep the AC cooling properly. I guess that's why they went to electric fans later.

 

[Marky Dissod]

Even with a good working fan clutch, there is sometimes not enough air flow at idle to keep the AC cooling properly.

How to install E-Fans

Step 1 - Pop hood Step 2 - Remove intake tube (This is only IF you want extra space...I didnt pull mine this time but you might want to) Step 3 - Remove two top bolts and pull coolant line clip out of shroud Step 4 - The Fan Shroud is two pieces. A top and a bottom. They are connected...

www.tahoeyukonforum.com

I installed E-fans on my 2001

How-To: Installing 06 E-fans on a 2001 This is a step by step tutorial on how to upgrade any 00-02 Tahoe, Yukon, or Suburban to the 05-06 GMT800 electric cooling fans. This same setup can be used on 03-04 trucks as well, however the only difference is the wiring that connects to the PCM. I...

www.tahoeyukonforum.com

Far superior to adding an electric pusher fan in front of the AC condenser as per a GM Tech Service Bulletin, whose reference number escapes me ...

AHA!
010139004A

 

[Marky Dissod]

01-01-39-004A Chevrolet Anti-Lock Brake Technical Service Bulletin

01-01-39-004A Chevrolet Anti-Lock Brake Technical Service Bulletin

www.tsbsearch.com

#01-01-39-004A: A/C Not Cold Enough, A/C Blows Warm Air with Vehicle at Extended Idle (Install Auxiliary Electric Coolant Fan) - (Dec 20, 2002)
Subject: A/C Not Cold Enough, A/C Blows Warm Air with Vehicle at Extended Idle (Install Auxiliary Electric Coolant Fan)
Models: 2002-2003 Cadillac Escalade, 2000-2003 Chevrolet Suburban, Tahoe, 2000-2003 GMC Yukon, Yukon XL, with 6.0L Engine (VINs U, N -- RPOs LQ4, LQ9)
This bulletin is being revised to add 2003 model year information and 2003 model year installation instructions.
Please discard Corporate Bulletin Number 01-01-39-004 (Section 01 -- HVAC).
Condition: Some customers may comment that the A/C blows warm air when idling for an extended period of time such as sitting in traffic.
Cause: Inadequate airflow over the condenser may cause this condition.
Correction: The addition of an auxiliary fan in front of the condenser radiator assembly may help to alleviate this condition.
The coolant fan will come on each time the A/C compressor is commanded on by the PCM.